Back to 2008 Lexus IS 250

2008 LEXUS IS 250

2.5L V6RWDAUTOMATICgas
5 active safety recalls on this vehicle — view recalls
Repairs0Labor505Torque3865Fluid7DTC882Battery0Maintenance0Recalls5
P1605high severityPowertrain

Knock Control CPU Malfunction

on 2008 Lexus IS 250 2.5L V6 · RWD

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

  1. Test knock sensor
  2. Inspect wiring harness
  3. Check ECM operation
  4. Monitor knock retard

Repair notes

Replace knock sensor or ECM.

Other Powertrain codes on this vehicle

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