Clutch Actuator Circuit High
The P0903 code indicates that the Powertrain Control Module (PCM) has detected a high voltage or resistance in the clutch actuator circuit. This circuit controls the clutch engagement and disengagement in automated manual transmissions (AMT) or some dual-clutch transmissions. A high circuit condition typically means the voltage signal from the actuator is above the expected range, often due to wiring issues, a faulty actuator, or a PCM problem.
01. Most Common Causes
- Faulty clutch actuator
- Open or shorted wiring in the clutch actuator circuit
- Corroded or loose electrical connectors
- Failed PCM
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Transmission not shifting properly or stuck in gear
- Clutch slippage or failure to engage/disengage
- Reduced fuel economy
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for other related codes.
Step 2: Visually inspect the clutch actuator wiring and connectors for damage, corrosion, or loose connections.
Step 3: Test the clutch actuator resistance and voltage with a multimeter and compare to manufacturer specifications.
Step 4: If wiring and actuator are okay, test the PCM output to the actuator circuit.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The transmission may fail to shift properly, causing loss of power or unexpected gear engagement, which can lead to an accident.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and minor repairs like connector cleaning, but could be higher if the clutch actuator or PCM needs replacement.