Audi DTC P1797 – Vehicle Speed Signal Circuit Short to B+
DTC P1797 meaning on Audi
The Diagnostic Trouble Code (DTC) P1797 for Audi indicates a Vehicle Speed Signal Circuit Short to B+. This means that there is a malfunction in the circuit that transmits the vehicle speed signal to the engine control module (ECM), and it is shorted to the battery positive voltage.
Audi DTC P1797 symptoms
Symptoms of DTC P1797 on an Audi may include:
- Speedometer not working
- Check Engine Light (CEL) illuminated
- Loss of cruise control functionality
- Erratic shifting behavior in automatic transmissions
Audi DTC P1797 causes
The common causes of DTC P1797 on an Audi are:
- Short circuit in the vehicle speed sensor wiring
- Defective vehicle speed sensor
- Faulty engine control module (ECM)
- Corrosion or poor connections in the speed sensor circuit
Audi DTC P1797 seriousness
The seriousness of DTC P1797 on an Audi depends on the driving conditions and the extent of the issue. While the vehicle may still be operable with this fault, it is important to address it promptly to prevent further damage to the vehicle’s systems.
How to diagnose DTC P1797 on Audi
To diagnose DTC P1797 on an Audi, follow these steps:
- Use a diagnostic scanner to retrieve the fault codes stored in the ECM.
- Inspect the vehicle speed sensor wiring for any signs of damage or short circuits.
- Test the vehicle speed sensor using a multimeter to check for proper resistance values.
- Check the connections at the ECM for corrosion or poor contact.
How to fix DTC P1797 on Audi
To fix DTC P1797 on an Audi, you can:
- Repair any damaged wiring in the vehicle speed sensor circuit.
- Replace the faulty vehicle speed sensor with a new one.
- If the ECM is determined to be faulty, replace it with a new or remanufactured unit.
- Clean and secure all connections in the speed sensor circuit.
How to erase DTC P1797 on Audi
To erase DTC P1797 on an Audi, you can:
- Use a diagnostic scanner to clear the fault codes stored in the ECM.
- After making the necessary repairs, drive the vehicle to ensure the issue does not reoccur.
- If the problem persists, further diagnosis may be required to address any underlying issues.
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