P0904high severityPowertrain
Gate Select Actuator Circuit Range/Performance
on 2017 Audi S5 3.0L Supercharged V6 · AWD
What this code means
The gate select actuator signal is out of the expected range or responding poorly. The transmission may not shift smoothly or reach the correct gear position.
Symptoms
- Delayed gear engagement
- Erratic shifting
- Reduced performance
Common causes
- Worn gate select actuator
- Wiring resistance issues
- Contaminated transmission fluid
- Faulty transmission control module
Diagnostic steps
- Retrieve freeze frame data
- Monitor actuator position values
- Inspect wiring and connectors
- Verify fluid level and condition
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