P0654
Engine RPM Output Circuit Open
The engine RPM signal output that the ECU sends to other modules (tachometer, transmission, ABS) has an open circuit.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: easy
Symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Common causes
Ordered by how often each turns out to be the cause.
- Open in output wiringCommon
- Pin pushed back out of connector bodyLess likely
- Cracked solder joint inside the module or sensorLess likely
Parts involved
- Engine Rpm Output
P0654 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.