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
Using the AUX port
To use the AUX port, connect a portable player, press the
“AUDIO” button, then select “AUX” to display the audio control
screen.
Connecting a portable audio player
Operating portable audio players connected to the audio system
The volume can be adjusted using the vehicle’s audio contr ...
Installing child restraints using a seat belt (child restraint lock
function belt)
Rear facing - Infant seat/convertible seat
Place the child restraint system
on the rear seat facing
the rear of the vehicle.
Run the seat belt through the
child restraint system and
insert the plate into the
buckle. Make sure that the
belt is not twisted.
Full ...
Terminals of ECU
1. CHECK POWER BACK DOOR ECU
Disconnect the P13 and P14 ECU connectors, and
check the voltage and resistance of each terminal of
the wire harness side connectors
If the result is not as specified, there may be a
malfunction on the wire harness side.
Reconnect the ECU co ...