What does code P1605 mean?

Q: What does code P1605 mean?

Knock Control CPU. P1605 on Toyota vehicles indicates that the engine control module (ECM) has detected an internal fault within its knock control CPU, which is the dedicated processor that manages ignition timing based on knock sensor input. The ECM runs a self-test on this CPU and sets the code when the processor fails to respond correctly or its calculations fall outside expected parameters.

DTC codes / Toyota codes / P1605

P1605 · ToyotaKnock Control CPU

P1605 on Toyota vehicles indicates that the engine control module (ECM) has detected an internal fault within its knock control CPU, which is the dedicated processor that manages ignition timing based on knock sensor input. The ECM runs a self-test on this CPU and sets the code when the processor fails to respond correctly or its calculations fall outside expected parameters.

SystemPowertrain

Code typeToyota specific

SeverityMedium

Fix difficultyProfessional

AreaComputer and output circuits

Guidance is general and written for Toyota vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.