What Causes The P173E00 Audi Fault Code?

The P173e00 Audi Fault Code signifies “Valve 2 in partial transmission electrical error,” often indicating issues within the transmission’s valve body or related electrical components. Fixing this promptly is crucial to prevent further damage. This in-depth guide will help you understand the causes, diagnostic steps, and potential solutions for this fault code, ensuring efficient and effective repairs, and AutoExplain.com provides expert remote support to troubleshoot and resolve this issue quickly.

1. What Does the Audi Fault Code P173E00 Mean?

The Audi fault code P173E00 means that there is a “Valve 2 in partial transmission electrical error” in the transmission system. This typically indicates a problem with the electrical circuit or the valve itself within the transmission’s valve body, which controls hydraulic pressure to shift gears.

• Detailed Explanation: The transmission valve body contains numerous solenoids and valves that regulate the flow of transmission fluid to various parts of the transmission, enabling gear changes. When the Engine Control Unit (ECU) detects an electrical fault in Valve 2, it triggers the P173E00 code. This fault could be due to a range of issues, including a faulty solenoid, damaged wiring, or a problem within the transmission control module (TCM).
• Symptoms Associated with P173E00: Common symptoms include harsh or erratic shifting, the transmission getting stuck in a gear, complete failure to shift, a noticeable decline in fuel efficiency, and the illumination of the check engine light on the dashboard. The vehicle might also enter limp mode to prevent further damage.
• Impact on Vehicle Performance: The fault code can significantly affect the vehicle’s drivability. Issues such as delayed gear shifts, unpredictable shifting patterns, and the inability to properly accelerate can make driving unsafe. In severe cases, the transmission may completely fail, rendering the vehicle immobile.

2. What Are the Common Causes of the P173E00 Error Code?

The P173E00 error code in Audi vehicles can be caused by several issues, primarily related to electrical and mechanical faults within the transmission system. Here are the most common causes:

1. Faulty Solenoid Valve:

   • The solenoid valve controls the flow of transmission fluid. If it malfunctions, it can cause the P173E00 code.
   • Explanation: Solenoid valves are electromechanical components that open and close to allow or restrict the flow of transmission fluid. A faulty solenoid can result from electrical failure (short circuit, open circuit) or mechanical issues (valve sticking, blockage).
   • Diagnostic Steps: Use a multimeter to check the solenoid’s resistance. Compare the reading with the manufacturer’s specifications. Also, inspect the solenoid for physical damage or debris.

2. Wiring Issues:

   • Damaged, corroded, or loose wiring connected to the transmission can trigger the P173E00 code.
   • Explanation: The wiring harness that connects the solenoid valve to the TCM can suffer from wear and tear, leading to breaks, shorts, or corrosion. These issues disrupt the electrical signal, causing the fault code.
   • Diagnostic Steps: Perform a visual inspection of the wiring harness for any signs of damage. Use a multimeter to check for continuity and voltage at the solenoid connector. Repair or replace any damaged wiring.

3. Contaminated Transmission Fluid:

   • Dirty or old transmission fluid can cause valves to stick or malfunction, leading to the P173E00 code.
   • Explanation: Contaminated transmission fluid contains particles that can clog the narrow passages within the valve body, preventing the solenoid valve from operating correctly.
   • Diagnostic Steps: Check the condition of the transmission fluid. If it appears dark, smells burnt, or contains debris, a transmission fluid flush and filter replacement are necessary.

4. Transmission Control Module (TCM) Failure:

   • A failing TCM can send incorrect signals to the solenoid valve, triggering the P173E00 code.
   • Explanation: The TCM controls the operation of the transmission based on input from various sensors. If the TCM malfunctions due to internal faults or software issues, it can lead to incorrect signals being sent to the solenoid valves.
   • Diagnostic Steps: Use a diagnostic scanner to check for other TCM-related fault codes. Perform a TCM reset or reprogramming if possible. If the problem persists, the TCM may need replacement.

5. Valve Body Issues:

   • Internal issues within the valve body, such as worn or sticking valves, can cause the P173E00 code.
   • Explanation: The valve body houses the solenoid valves and mechanical valves that control transmission fluid flow. Wear and tear or contamination can cause these valves to stick or fail, leading to incorrect hydraulic pressure and shifting problems.
   • Diagnostic Steps: Remove and inspect the valve body for signs of wear, damage, or contamination. Clean the valve body thoroughly or replace it if necessary.

6. Low Transmission Fluid Level:

   • Insufficient transmission fluid can cause erratic shifting and trigger the P173E00 code.
   • Explanation: Low fluid levels can lead to reduced hydraulic pressure, causing the solenoid valves to operate inefficiently.
   • Diagnostic Steps: Check the transmission fluid level using the dipstick (if equipped) or the fill plug. Add fluid as needed to bring it to the correct level. Also, check for leaks that may be causing the low fluid level.

7. Mechanical Transmission Problems:

   • Internal mechanical failures within the transmission can indirectly cause the P173E00 code by affecting the hydraulic system.
   • Explanation: Issues such as worn clutches, damaged gears, or a failing torque converter can create abnormal pressure conditions that affect the solenoid valves.
   • Diagnostic Steps: Perform a thorough inspection of the transmission for any signs of mechanical damage. This may require removing the transmission pan to inspect internal components.

By systematically diagnosing these potential causes, you can accurately pinpoint the source of the P173E00 error code and implement the appropriate repairs. AutoExplain.com is available to provide expert guidance and support throughout the diagnostic and repair process.

3. How To Diagnose The P173E00 Fault Code?

Diagnosing the P173E00 fault code requires a systematic approach to identify the root cause. Here are the steps to effectively diagnose the issue:

1. Initial Scan and Code Verification:

   • Action: Use an OBD-II scanner to read and record all stored fault codes.
   • Details: Connect the scanner to the vehicle’s OBD-II port and retrieve all active and pending codes. Note down the codes and their order of appearance. Clear the codes and take the vehicle for a test drive to see if the P173E00 code reappears. This confirms the code and helps identify if it’s an intermittent or constant issue.

2. Visual Inspection:

   • Action: Conduct a thorough visual inspection of the transmission components and wiring.
   • Details: Check the transmission housing for any signs of damage or leaks. Inspect the wiring harness connected to the transmission for frayed wires, corrosion, or loose connections. Pay close attention to the wiring near heat sources or moving parts that could cause damage.

3. Check Transmission Fluid Level and Condition:

   • Action: Inspect the transmission fluid for proper level and condition.
   • Details: Use the transmission fluid dipstick (if equipped) to check the fluid level. The fluid should be at the “full” mark. Examine the fluid’s color and smell. Healthy transmission fluid is typically red and has a slightly sweet odor. Dark, burnt-smelling fluid indicates contamination or overheating, which can affect valve performance.

4. Solenoid Valve Testing:

   • Action: Test the solenoid valve for electrical continuity and resistance.
   • Details: Locate the solenoid valve associated with Valve 2 within the transmission valve body. Use a multimeter to measure the resistance across the solenoid terminals. Compare the reading with the manufacturer’s specifications. An open circuit or short circuit indicates a faulty solenoid. Also, check for continuity to ground, which would indicate a short to ground.

5. Wiring Harness and Connector Testing:

   • Action: Test the wiring harness and connectors for continuity, voltage, and proper connection.
   • Details: Disconnect the wiring harness from the solenoid valve and the TCM. Use a multimeter to check for continuity between the TCM connector and the solenoid connector. Check for shorts to ground by testing for continuity between each wire and the vehicle’s chassis ground. Verify that the correct voltage is reaching the solenoid valve when commanded by the TCM.

6. Transmission Control Module (TCM) Diagnosis:

   • Action: Diagnose the TCM for proper operation and software issues.
   • Details: Use a diagnostic scanner to check for any TCM-specific fault codes. Perform a TCM reset or reprogramming if possible. Monitor the TCM’s input and output signals to ensure they are within the expected range. If the TCM is suspected of malfunctioning, consider having it tested by a specialized repair shop or replacing it with a new unit.

7. Valve Body Inspection:

   • Action: Inspect the valve body for mechanical issues and contamination.
   • Details: Remove the transmission pan to access the valve body. Carefully inspect the valve body for any signs of wear, damage, or contamination. Check the valves for smooth movement and ensure they are not sticking. Clean the valve body with a specialized solvent if necessary.

8. Hydraulic Pressure Testing:

   • Action: Perform a hydraulic pressure test to check the transmission’s hydraulic system.
   • Details: Connect a hydraulic pressure gauge to the test ports on the transmission. Measure the pressure at various points in the system while the transmission is operating. Compare the readings with the manufacturer’s specifications. Low or erratic pressure can indicate issues with the pump, valve body, or internal transmission components.

By following these detailed diagnostic steps, you can accurately identify the cause of the P173E00 fault code and perform the necessary repairs. AutoExplain.com offers remote diagnostic support to guide you through each step, ensuring a precise and efficient diagnosis.

4. Step-by-Step Guide to Fix the P173E00 Error

Fixing the P173E00 error code requires addressing the underlying cause identified during the diagnostic process. Here’s a step-by-step guide to help you resolve the issue:

1. Address Wiring Issues:

   • Step 1: Inspect Wiring Harness:

     • Check the wiring harness connected to the transmission for any signs of damage, such as frayed wires, corrosion, or loose connections.
     • Repair or replace any damaged sections of the wiring harness. Use high-quality electrical tape or heat shrink tubing to protect the repaired wires.

   • Step 2: Clean Connectors:

     • Clean the electrical connectors with a specialized electrical contact cleaner.
     • Ensure the connectors are securely attached to the solenoid valve and the TCM.

2. Replace Faulty Solenoid Valve:

   • Step 1: Locate and Access the Solenoid Valve:

     • Identify the solenoid valve associated with Valve 2 within the transmission valve body.
     • Remove the transmission pan to access the valve body.

   • Step 2: Replace the Solenoid Valve:

     • Disconnect the electrical connector from the solenoid valve.
     • Remove the solenoid valve from the valve body.
     • Install a new, OEM-quality solenoid valve.
     • Reconnect the electrical connector.

3. Perform Transmission Fluid Flush and Filter Replacement:

   • Step 1: Drain the Old Transmission Fluid:

     • Remove the transmission pan drain plug to drain the old transmission fluid.
     • Allow the fluid to drain completely.

   • Step 2: Replace the Transmission Filter:

     • Remove the transmission pan.
     • Remove the old transmission filter.
     • Install a new, OEM-quality transmission filter.

   • Step 3: Reinstall the Transmission Pan and Refill with New Fluid:

     • Clean the transmission pan and install a new gasket.
     • Reinstall the transmission pan.
     • Refill the transmission with the correct type and amount of transmission fluid as specified by the vehicle manufacturer.

4. Repair or Replace Valve Body:

   • Step 1: Remove the Valve Body:

     • Disconnect the electrical connectors and hydraulic lines from the valve body.
     • Remove the valve body from the transmission.

   • Step 2: Inspect and Clean the Valve Body:

     • Inspect the valve body for wear, damage, or contamination.
     • Clean the valve body with a specialized solvent to remove any debris.

   • Step 3: Reinstall or Replace the Valve Body:

     • If the valve body is in good condition, reinstall it with new gaskets.
     • If the valve body is damaged or worn, replace it with a new or remanufactured unit.
     • Reconnect the electrical connectors and hydraulic lines.

5. Address TCM Issues:

   • Step 1: Check for TCM Software Updates:

     • Use a diagnostic scanner to check for any available software updates for the TCM.
     • Update the TCM software if necessary.

   • Step 2: Reprogram or Replace the TCM:

     • If the TCM is malfunctioning, attempt to reprogram it using a diagnostic scanner.
     • If reprogramming fails, replace the TCM with a new or refurbished unit.
     • Ensure the new TCM is properly programmed to match the vehicle’s specifications.

6. Verify Repair and Clear Codes:

   • Step 1: Test Drive the Vehicle:

     • Take the vehicle for a test drive to ensure the transmission is shifting smoothly and the P173E00 code does not reappear.

   • Step 2: Clear Fault Codes:

     • Use an OBD-II scanner to clear any remaining fault codes from the vehicle’s computer.

By following these steps, you can effectively address the P173E00 error code and restore your vehicle’s transmission to proper working order. AutoExplain.com provides expert remote support to guide you through each step of the repair process.

5. What Are the Tools Needed to Fix the P173E00 Code?

To effectively diagnose and repair the P173E00 code, you’ll need a variety of tools. Having the right tools ensures that you can accurately identify the problem and perform the necessary repairs. Here’s a list of essential tools:

1. OBD-II Scanner:

   • Purpose: To read and clear diagnostic trouble codes (DTCs).
   • Features: Should be able to read live data, perform component tests, and provide detailed code descriptions.
   • Example: Autel MaxiCOM MK808, Launch X431 V+.

2. Multimeter:

   • Purpose: To test electrical circuits for voltage, continuity, and resistance.
   • Features: Digital display, auto-ranging, and the ability to measure small electrical values.
   • Example: Fluke 115, Klein Tools MM400.

3. Socket Set:

   • Purpose: To remove and install bolts and nuts on the transmission and related components.
   • Features: Both metric and standard sizes, various drive sizes (1/4″, 3/8″, 1/2″), and deep sockets for hard-to-reach areas.
   • Example: Craftsman 230-Piece Mechanic’s Tool Set, Stanley STMT71654.

4. Wrench Set:

   • Purpose: To loosen and tighten bolts and nuts, especially in tight spaces.
   • Features: Includes open-end, box-end, and combination wrenches in various sizes.
   • Example: GearWrench 81910 14-Piece Metric Combination Wrench Set, Tekton 25282 Combination Wrench Set.

5. Torque Wrench:

   • Purpose: To tighten bolts and nuts to the manufacturer’s specified torque.
   • Features: Accurate torque measurement, adjustable settings, and clear scale markings.
   • Example: CDI Torque 1002CF3 Drive Click Torque Wrench, Precision Instruments PREC3FR250F Torque Wrench.

6. Transmission Fluid Pan Wrench:

   • Purpose: To remove and install the transmission fluid pan without damaging it.
   • Features: Specific size and design to fit the transmission pan bolts.

7. Transmission Fluid Pump:

   • Purpose: To refill the transmission with new fluid.
   • Features: Hand-operated or electric pump with a hose that fits into the transmission fill port.

8. Pliers:

   • Purpose: To grip, cut, and manipulate wires and small parts.
   • Features: Includes needle-nose pliers, diagonal cutting pliers, and slip-joint pliers.
   • Example: Klein Tools D213-9NE High-Leverage Side-Cutting Pliers, Channellock Tool Set.

9. Screwdriver Set:

   • Purpose: To remove and install screws on various components.
   • Features: Includes both Phillips-head and flat-head screwdrivers in multiple sizes.
   • Example: Wiha 32091 Screwdriver Set, Craftsman Screwdriver Set.

10. Pick and Hook Set:

    • Purpose: To remove O-rings, seals, and small parts from tight spaces.
    • Features: Includes various hook and pick shapes for different applications.

11. Inspection Mirror:

    • Purpose: To inspect hard-to-see areas for damage or corrosion.
    • Features: Extendable handle and adjustable mirror angle.

12. Parts Cleaner:

    • Purpose: To clean the valve body and other transmission components.
    • Features: Non-chlorinated formula, safe for use on electrical components.

13. Transmission Jack:

    • Purpose: To support and remove the transmission safely.
    • Features: Adjustable height, wide base for stability, and safety chains.

14. Wheel Chocks:

    • Purpose: To secure the vehicle and prevent it from rolling.
    • Features: Durable construction, non-slip surface.

Having these tools on hand will enable you to efficiently and accurately diagnose and repair the P173E00 code. If you need further assistance or guidance, AutoExplain.com offers expert remote support to help you through the process.

6. What Are the Costs to Repair the P173E00 Fault Code?

The cost to repair the P173E00 fault code can vary significantly depending on the underlying issue and the extent of the repair needed. Here’s a breakdown of potential costs associated with different repair scenarios:

1. Wiring Repair:

   • Description: Repairing damaged, corroded, or loose wiring connected to the transmission.
   • Parts: Cost of wiring, connectors, and electrical tape or heat shrink tubing.
   • Labor: $50 – $200
   • Total: $50 – $250

2. Solenoid Valve Replacement:

   • Description: Replacing a faulty solenoid valve within the transmission valve body.
   • Parts: OEM-quality solenoid valve ($100 – $300).
   • Labor: $150 – $400 (depending on the location and accessibility of the valve).
   • Total: $250 – $700

3. Transmission Fluid Flush and Filter Replacement:

   • Description: Draining the old transmission fluid, replacing the filter, and refilling with new fluid.
   • Parts: Transmission fluid (typically $5 – $15 per quart, requiring 5-10 quarts), transmission filter ($20 – $50).
   • Labor: $100 – $250
   • Total: $125 – $400

4. Valve Body Repair or Replacement:

   • Description: Repairing or replacing the transmission valve body.
   • Parts: Valve body repair kit ($50 – $150) or a new/remanufactured valve body ($400 – $1200).
   • Labor: $300 – $800
   • Total: $350 – $1350

5. Transmission Control Module (TCM) Reprogramming or Replacement:

   • Description: Reprogramming or replacing the TCM.
   • Parts: Reprogramming fee ($50 – $200) or a new/refurbished TCM ($300 – $1000).
   • Labor: $100 – $300
   • Total: $150 – $1300

6. Full Transmission Replacement:

   • Description: Replacing the entire transmission due to extensive damage.
   • Parts: New or remanufactured transmission ($2000 – $5000).
   • Labor: $500 – $1500
   • Total: $2500 – $6500

7. Diagnostic Fees:

   • Description: Cost for initial diagnosis to determine the cause of the P173E00 code.
   • Fees: $75 – $150 (can sometimes be applied to the repair cost if you proceed with the service).

Factors Affecting Cost:

• Vehicle Make and Model: Luxury or high-performance vehicles may have more expensive parts and require specialized labor.
• Shop Location: Labor rates vary by region, with urban areas typically having higher rates.
• Dealership vs. Independent Mechanic: Dealerships often have higher labor rates but may offer specialized expertise.
• Warranty Coverage: Check if your vehicle is under warranty, as this could cover some or all of the repair costs.

By considering these potential costs and factors, you can better prepare for the expense of repairing the P173E00 fault code. AutoExplain.com offers expert remote support to help you diagnose the issue accurately and explore cost-effective repair options.

7. Can I Drive My Audi With the P173E00 Fault Code?

Driving with the P173E00 fault code is not recommended because it indicates a significant issue within the transmission system. Continuing to drive with this code can lead to further damage and potentially leave you stranded. Here’s why:

• Erratic Shifting: The P173E00 code often results in erratic or harsh shifting. The transmission may not shift properly, causing the vehicle to lurch or jerk unexpectedly. This can make driving unsafe, especially in heavy traffic or at high speeds.
• Limp Mode: To protect itself from further damage, the transmission may enter limp mode, which limits the vehicle’s speed and performance. In limp mode, the transmission typically locks into a single gear, reducing your ability to accelerate or maintain speed on the highway.
• Transmission Damage: The underlying issue causing the P173E00 code, such as a faulty solenoid valve or contaminated transmission fluid, can lead to increased wear and tear on the transmission components. Continuing to drive with these issues can cause more extensive and costly damage.
• Safety Risks: The unpredictable behavior of the transmission can create hazardous driving conditions, increasing the risk of accidents. It’s best to address the problem promptly to ensure your safety and the safety of others on the road.

What to Do:

1. Stop Driving: If the P173E00 code appears, it’s best to stop driving as soon as it is safe to do so.
2. Diagnostic Scan: Use an OBD-II scanner to read and record all stored fault codes. This will help you understand the extent of the problem.
3. Professional Inspection: Take your vehicle to a trusted mechanic or service center for a professional inspection. They can accurately diagnose the issue and recommend the necessary repairs.
4. Repair Immediately: Address the underlying cause of the P173E00 code as soon as possible to prevent further damage and ensure safe driving conditions.

Ignoring the P173E00 fault code can lead to more severe and expensive problems down the road. AutoExplain.com offers expert remote support to help you diagnose the issue and determine the best course of action.

8. How to Prevent the P173E00 Error Code from Appearing?

Preventing the P173E00 error code involves proactive maintenance and care of your vehicle’s transmission system. Here are some effective strategies to keep this issue at bay:

1. Regular Transmission Fluid Checks:

   • Action: Check the transmission fluid level and condition regularly.
   • Details: Use the transmission fluid dipstick (if equipped) to check the fluid level. The fluid should be at the “full” mark. Examine the fluid’s color and smell. Healthy transmission fluid is typically red and has a slightly sweet odor. Dark, burnt-smelling fluid indicates contamination or overheating.
   • Frequency: Check the fluid every 30,000 miles or as recommended by the vehicle manufacturer.

2. Scheduled Transmission Fluid Flushes:

   • Action: Perform transmission fluid flushes and filter replacements at recommended intervals.
   • Details: Follow the manufacturer’s recommended service intervals for transmission fluid flushes and filter replacements. This helps remove contaminants and keeps the transmission operating smoothly.
   • Frequency: Typically every 30,000 to 60,000 miles, depending on driving conditions and manufacturer recommendations.

3. Avoid Harsh Driving Habits:

   • Action: Avoid aggressive driving behaviors that can stress the transmission.
   • Details: Minimize hard acceleration, abrupt stops, and frequent gear changes. These habits can cause excessive wear and tear on the transmission components.

4. Proper Vehicle Warm-Up:

   • Action: Allow the engine and transmission to warm up properly before driving.
   • Details: In cold weather, let the engine idle for a few minutes before driving to allow the transmission fluid to circulate and warm up. This helps ensure proper lubrication and reduces stress on the transmission components.

5. Address Leaks Promptly:

   • Action: Monitor for any signs of transmission fluid leaks and address them immediately.
   • Details: Check for leaks around the transmission housing, seals, and connections. Leaks can lead to low fluid levels, which can cause erratic shifting and trigger the P173E00 code.

6. Use OEM-Quality Parts:

   • Action: When replacing transmission components, use OEM-quality parts.
   • Details: OEM (Original Equipment Manufacturer) parts are designed to meet the vehicle’s specifications and ensure proper fit and performance. Using aftermarket parts can sometimes lead to compatibility issues and premature failure.

7. Regular Maintenance Checks:

   • Action: Schedule regular maintenance checks with a trusted mechanic.
   • Details: A professional mechanic can inspect the transmission system for any potential issues and perform necessary maintenance to keep it running smoothly.

8. Avoid Overloading the Vehicle:

   • Action: Avoid overloading the vehicle beyond its specified weight capacity.
   • Details: Overloading can put excessive strain on the transmission, leading to overheating and premature wear.

9. Check for Software Updates:

   • Action: Ensure that the TCM has the latest software updates.
   • Details: Software updates can improve the transmission’s performance and prevent issues that could trigger the P173E00 code.

By following these preventive measures, you can significantly reduce the risk of encountering the P173E00 error code and keep your vehicle’s transmission in optimal condition. AutoExplain.com offers expert advice and support to help you maintain your vehicle’s transmission system.

9. What Are Other Fault Codes Related To Transmission Issues?

Several other fault codes are related to transmission issues and can sometimes appear alongside or in conjunction with the P173E00 code. Understanding these related codes can provide a more comprehensive picture of the transmission’s health. Here are some common fault codes associated with transmission problems:

1. P0700 – Transmission Control System Malfunction:

   • Description: This is a generic code indicating that the transmission control system has detected a fault.
   • Symptoms: Check engine light, erratic shifting, transmission slipping, or failure to shift.
   • Possible Causes: Faulty TCM, wiring issues, solenoid problems, or mechanical failures within the transmission.

2. P0715 – Input/Turbine Speed Sensor Circuit Malfunction:

   • Description: This code indicates a problem with the input speed sensor, which monitors the speed of the transmission’s input shaft.
   • Symptoms: Erratic shifting, transmission slipping, or failure to shift.
   • Possible Causes: Faulty input speed sensor, wiring issues, or TCM problems.

3. P0720 – Output Speed Sensor Circuit Malfunction:

   • Description: This code indicates a problem with the output speed sensor, which monitors the speed of the transmission’s output shaft.
   • Symptoms: Erratic shifting, speedometer issues, or failure to shift.
   • Possible Causes: Faulty output speed sensor, wiring issues, or TCM problems.

4. P0741 – Torque Converter Clutch Circuit Performance or Stuck Off:

   • Description: This code indicates a problem with the torque converter clutch (TCC) circuit, which controls the engagement and disengagement of the TCC.
   • Symptoms: Reduced fuel economy, overheating, or erratic shifting.
   • Possible Causes: Faulty TCC solenoid, wiring issues, or mechanical problems with the torque converter.

5. P0750 – Shift Solenoid A Malfunction:

   • Description: This code indicates a problem with shift solenoid A, which controls the flow of hydraulic fluid to shift gears.
   • Symptoms: Erratic shifting, transmission slipping, or failure to shift.
   • Possible Causes: Faulty shift solenoid, wiring issues, or TCM problems.

6. P0775 – Pressure Control Solenoid B Malfunction:

   • Description: This code indicates a problem with pressure control solenoid B, which regulates the hydraulic pressure within the transmission.
   • Symptoms: Harsh shifting, transmission slipping, or failure to shift.
   • Possible Causes: Faulty pressure control solenoid, wiring issues, or TCM problems.

7. P0841 – Transmission Fluid Pressure Sensor/Switch A Circuit Range/Performance:

   • Description: This code indicates a problem with the transmission fluid pressure sensor, which monitors the pressure of the transmission fluid.
   • Symptoms: Erratic shifting, transmission slipping, or failure to shift.
   • Possible Causes: Faulty pressure sensor, wiring issues, or TCM problems.

8. P173F – Valve 2 in Partial Transmission 1 Electrical Error:

   • Description: Valve 2 in partial transmission electrical error.
   • Symptoms: Check engine light, shift problems.
   • Possible Causes: Open or shorted circuit condition, poor electrical connection, faulty solenoid.

9. U0101 – Lost Communication With TCM:

   • Description: This code indicates a loss of communication between the TCM and other modules in the vehicle.
   • Symptoms: Check engine light, transmission problems, or other system malfunctions.
   • Possible Causes: Wiring issues, faulty TCM, or network problems.

Understanding these related fault codes can help you diagnose transmission issues more effectively and ensure that all underlying problems are addressed. AutoExplain.com offers expert remote support to help you navigate complex diagnostic scenarios.

10. FAQ About The P173E00 Audi Fault Code

Here are some frequently asked questions (FAQs) about the P173E00 Audi fault code to help you better understand the issue and how to address it:

1. What does the P173E00 fault code specifically mean for an Audi?

   • The P173E00 fault code in an Audi indicates a “Valve 2 in partial transmission electrical error.” This typically means there is an electrical issue with the solenoid valve that controls the hydraulic pressure for shifting gears in the transmission.

2. Can low transmission fluid cause the P173E00 code?

   • Yes, low transmission fluid can contribute to the P173E00 code. Insufficient fluid levels can lead to reduced hydraulic pressure, causing the solenoid valves to operate inefficiently and trigger the fault code.

3. Is it safe to drive my Audi with the P173E00 code?

   • No, it is generally not safe to drive with the P173E00 code. The transmission may exhibit erratic shifting or enter limp mode, which can be dangerous, especially in heavy traffic.

4. How often should I change my Audi’s transmission fluid to prevent issues like P173E00?

   • It is recommended to change your Audi’s transmission fluid every 30,000 to 60,000 miles, depending on driving conditions and the manufacturer’s recommendations. Regular fluid changes help prevent contamination and maintain proper transmission function.

5. Can a faulty TCM cause the P173E00 error?

   • Yes, a faulty Transmission Control Module (TCM) can cause the P173E00 error. The TCM controls the operation of the transmission, and if it malfunctions, it can send incorrect signals to the solenoid valves.

6. What are the first steps I should take when the P173E00 code appears?

   • The first steps should include scanning the vehicle with an OBD-II scanner to confirm the code, visually inspecting the transmission and wiring, and checking the transmission fluid level and condition.

7. Can I fix the P173E00 code myself, or do I need a professional mechanic?

   • While some repairs, like checking fluid levels or replacing a solenoid valve, can be done by experienced DIYers, it’s often best to consult a professional mechanic. Transmission issues can be complex, and incorrect repairs can cause further damage.

8. What is the typical cost to repair the P173E00 fault code in an Audi?

   • The cost to repair the P173E00 code can range from $250 to $700 for a solenoid valve replacement, but it can be higher if the issue is with the TCM or valve body. A full transmission replacement can cost between $2500 and $6500.

9. Are there any temporary fixes for the P173E00 code?

   • There are no reliable temporary fixes for the P173E00 code. Addressing the underlying issue is crucial to prevent further damage and ensure safe driving.

10. How can AutoExplain.com help me with the P173E00 fault code?

    • AutoExplain.com offers expert remote support to help you diagnose the cause of the P173E00 code, provides step-by-step repair guidance, and assists with TCM reprogramming or replacement. Contact us via WhatsApp at (+84)967469410 or email at AutoExplain[email protected] for assistance.

By addressing these FAQs, you can gain a better understanding of the P173E00 Audi