DTC P0606 ECM/PCM Processor: Description

The ECM continuously monitors its internal processors (CPUs), A/F sensor transistors and heated oxygen sensor (HO2S) transistors. This self-check ensures that the ECM is functioning properly. This is diagnosed by internal "mirroring" of the main and sub CPUs to detect processor errors. If outputs from the processors deviate from the standard, the ECM will illuminate the MIL and set a DTC immediately.

DTC DETECTION CONDITION CHART

DTC No.	DTC Detection Condition	Trouble Area
P0606	ECM CPUs malfunction A/F sensor transistors malfunction HO2S transistors malfunction	Exhaust gas leak HO2S ECM

NOTE: An exhaust gas leak generates noise in the HO2S output. The ECM may interpret this as an HO2S transistor malfunction and set P0606.