P0654: Engine RPM Output Circuit/Open
What to do
Driveable; the rev counter may read erratically or not at all while the engine runs normally. Mention any aftermarket alarm, tracker or immobiliser — this circuit is commonly tapped by them.
What this code means
A fault in the engine speed signal the module sends out — to the instrument cluster's tachometer, and sometimes to other systems that need engine speed.
As with the road speed outputs, aftermarket installations are a frequent cause because this is a convenient wire for a rev limiter, alarm or tracker to tap. A dead tachometer with the engine running perfectly is the characteristic presentation.
Likely causes
Start here
- Aftermarket device wired into the circuit · moderate
- Broken wire in control circuit · moderate
- Corroded or loose connector · easy
Less common
- Failed instrument cluster · specialist
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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