P0888
PowertrainTransmissionhigh severityTCM Power Relay Sense Circuit High
What P0888 Means
The transmission control module sees higher than expected voltage on the power relay sense circuit. This usually points to a stuck relay or a wiring fault.
Symptoms
- Transmission warning light on
- Shifting problems or limp mode
- Relay may stay energized
Common Causes
- Stuck or shorted TCM power relay
- Wiring short to voltage on sense circuit
- Corroded relay connectors
- Faulty transmission control module
Diagnostic Steps
- Scan for related transmission codes
- Test TCM power relay operation
- Measure sense circuit voltage
- Inspect wiring for short to power
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✓ Autel official store
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