P1605high severityPowertrain
Knock Control CPU Malfunction
on 1992-2006 Lexus ES 300 3.0L V6 · FWD
What this code means
The ECM detected a communication failure with the knock control CPU.
Symptoms
- CEL
- Engine knock under load
- Reduced performance
- Timing retarded to safe value
Common causes
- Faulty knock CPU in ECM
- Damaged knock sensor wiring
- Faulty knock sensor
- Poor connections
Diagnostic steps
- Test knock sensor
- Inspect wiring harness
- Check ECM operation
- Monitor knock retard
Repair notes
Replace knock sensor or ECM.
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P0014
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P0015
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