DTC P0604 Internal Control Module Random Access Memory (RAM) Error
DESCRIPTION
The ECM continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check ensures that the ECM is functioning properly. If any malfunction is detected, the ECM sets the appropriate DTC and illuminates the MIL.
The ECM memory status is diagnosed by internal mirroring of the main CPU and the sub CPU to detect Random Access Memory (RAM) errors. The two CPUs also perform continuous mutual monitoring. The ECM illuminates the MIL and sets a DTC if: 1) outputs from the two CPUs are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ECM malfunction is found.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
ECM RAM errors:
INSPECTION PROCEDURE
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
1 CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0604)
Result
REPLACE ECM
Sound Signal Circuit between Radio Receiver and Stereo Component
Amplifier
DESCRIPTION
The radio receiver sends a sound signal to the stereo component amplifier
through this circuit.
The sound signal that has been sent is amplified by the stereo component
amplifier, and then is sent to
the speakers.
If there is an open or short in the circuit, sound cannot be h ...
Disassembly
1. REMOVE FRONT BUMPER ENERGY ABSORBER
2. REMOVE FRONT BUMPER REINFORCEMENT SUBASSEMBLY
Remove the 6 bolts and the front bumper
reinforcement sub-assembly.
3. REMOVE FRONT BUMPER SIDE SUPPORT LH
Remove the screw.
Disengage the 2 clips and remove the front bumper
side suppor ...
Intake Air Temperature Sensor Gradient Too High
DESCRIPTION
The Intake Air Temperature (IAT) sensor, mounted on the Mass Air Flow (MAF)
meter, monitors the IAT.
The IAT sensor has a built-in thermistor with a resistance that varies according
to the temperature of the
intake air. When the IAT becomes low, the resistance of the the ...