P0606

3UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0606: ECM / PCM Processor

DTC P0606 - ECM / PCM Processor

DESCRIPTION

The ECM continuously monitors its internal processors (CPUs), 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 standards, the ECM will illuminate the MIL and set a DTC immediately.





HINT: The MIL does not illuminate when a malfunction is detected in the CPU peripheral circuit of the ECM. It illuminate when a malfunction is detected in the ECM internal circuit: accelerator pedal position, brake switch, cruise control, heated oxygen sensor and throttle position.
NOTE: First check for an exhaust gas leak around the HO2S if P0606 is present. An exhaust gas leak generates noise in the HO2S output. The ECM may interpret this as an HO2S transistor malfunction and set P0606.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





INSPECTION PROCEDURE

PROCEDURE

1. CHECK FOR EXHAUST GAS LEAK
(a) Allow the engine to idle.
(b) Check for an exhaust gas leak around the HO2S.
OK:
No leak from the HO2S.
NG -- REPAIR LEAK
OK -- Continue to next step.
2. CHECK HEATED OXYGEN SENSOR





(a) Warm up the engine.
(b) Allow the engine to idle.
(c) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
(d) Check the O2S B1 S2 (O2S B2 S2) values when the Control the Injection Volume for A/F Sensor is -12.5% (Lean fuel-trim).
(e) Check the O2S B1 S2 (O2S B2 S2) values when the Control the Injection Volume for A/F Sensor is 25% (Rich fuel-trim).
Standard:






NG -- REPLACE HEATED OXYGEN SENSOR
OK -- Continue to next step.
3. CHECK DTC
(a) Clear DTC.
(b) Turn the ignition switch OFF.
(c) Disconnect the cable from the negative battery terminal and wait for 1 minute.
(d) Connect the cable to the negative battery terminal.
(e) Start the engine.





(f) Perform the drive pattern.
(1) Warm up the engine.
(2) Accelerate the vehicle until 80 km/h (50 mph) and stop the vehicle.
(3) Drive the vehicle by 60 to 80 km/h (35 to 50 mph) for 5 minutes or more.
(g) Check DTC.
OK:
P0606 is not present.
NG -- REPLACE ECM
OK -- CHECK FOR INTERMITTENT PROBLEMS