Audi DTC P1745 – Transmission Control Unit Relay Short to B+
DTC P1745 meaning on Audi
DTC P1745 on an Audi indicates a transmission control unit relay short to battery positive (B+). This fault code is specific to the transmission control module (TCM) and signifies an electrical issue within the relay circuit.
Audi DTC P1745 symptoms
Symptoms of DTC P1745 on an Audi may include erratic shifting behavior, transmission slipping, harsh shifting, or the transmission going into limp mode. The vehicle may also display a check engine light on the dashboard.
Audi DTC P1745 causes
The most common causes of DTC P1745 on an Audi are a faulty transmission control unit relay, damaged wiring or connectors in the relay circuit, or a short to battery positive within the TCM relay circuit.
Audi DTC P1745 seriousness
DTC P1745 should be addressed promptly as it can lead to drivability issues and potential damage to the transmission if left unresolved. Ignoring this fault code may result in further transmission problems and increased repair costs.
How to diagnose DTC P1745 on Audi
To diagnose DTC P1745 on an Audi, a mechanic would typically perform a thorough inspection of the transmission control unit relay and its associated wiring. Using a diagnostic scanner, the technician can retrieve the fault code and conduct further testing to pinpoint the exact cause of the issue.
- Check the transmission control unit relay for proper operation
- Inspect the wiring and connectors in the relay circuit for any damage or corrosion
- Use a multimeter to test for a short to battery positive in the TCM relay circuit
How to fix DTC P1745 on Audi
Fixing DTC P1745 on an Audi typically involves repairing or replacing the faulty transmission control unit relay and addressing any wiring issues in the relay circuit. The following steps can be taken to resolve this fault code:
- Replace the transmission control unit relay if it is found to be faulty
- Repair or replace any damaged wiring or connectors in the relay circuit
- Clear the fault code and test drive the vehicle to ensure the issue has been resolved
How to erase DTC P1745 on Audi
To erase DTC P1745 on an Audi, a diagnostic scanner can be used to clear the fault code from the transmission control module’s memory. After the repair has been completed and the issue resolved, follow these steps to erase the fault code:
- Connect the diagnostic scanner to the vehicle’s OBD-II port
- Select the option to clear fault codes from the TCM
- Confirm the action and wait for the scanner to erase the DTC P1745 code
- Once the code has been cleared, test drive the vehicle to ensure the fault does not reoccur
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