P0909
PowertrainTransmission Shifthigh severityGate Select Actuator Circuit High
What P0909 Means
The gate select actuator circuit is reading a high voltage condition. This suggests an open circuit or short to power affecting shift operation.
Symptoms
- Failed shifts
- Fault light illuminated
- Erratic gear behavior
Common Causes
- Open circuit in wiring
- Short to battery voltage
- Faulty actuator
- Faulty transmission control module
Diagnostic Steps
- Retrieve stored codes
- Inspect for open or shorted wiring
- Measure actuator supply voltage
- Test and replace actuator if needed
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✓ Autel official store
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