P0604

2GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0604: Internal Control Module Random Access Memory (RAM) Error
P0604 - Internal Control Module Random Access Memory (RAM) Error

DESCRIPTION

The ECM continuously monitors its internal memory status. This self-check ensures that the ECM is functioning properly. It is diagnosed by internal "mirroring" of the main CPU and sub CPU to detect the Random Access Memory (RAM) errors. If outputs from these CPUs are different and deviate from the standards, the ECM will illuminate the MIL and set a DTC immediately.





MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





CONFIRMATION DRIVING PATTERN





- Connect the Techstream to the DLC3.

- Turn the engine switch on (IG) and turn the Techstream on.

- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) DTC Check / Clear.

- Turn the engine switch off and wait for 30 seconds.

- Turn the engine switch on (IG) and turn the Techstream on.

- Wait 16 seconds or more [A].

- Enter the following menus: Powertrain / Engine / Trouble Codes.

- Read the DTC [B].

- If a DTC is output, the system is malfunctioning.

HINT
If a DTC is not output, perform the following procedure.

- Enter the following menus: Powertrain / Engine / Utility / All Readiness.

- Input the DTC: P0604.

- Check the DTC judgment result.





HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [A] again.
- Enter the following menus: Powertrain / Engine / Utility / All Readiness.

- Check the judgment result.

HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows NORMAL, the system is normal.
- If the test result is INCOMPLETE or UNKNOWN and no DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
INSPECTION PROCEDURE

PROCEDURE

1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0604)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Clear the DTC.

(e) Turn the engine switch off.

(f) Disconnect the battery negative terminal and wait for 1 minute.

(g) Connect the battery negative terminal.

(h) Turn the engine switch on (IG).

(i) Wait 16 seconds or more.

(j) Turn the Techstream on.

(k) Enter the following menus: Powertrain / Engine / Trouble Codes.

(l) Read the DTCs.

Result:





B -- CHECK FOR INTERMITTENT PROBLEMS

A -- REPLACE ECM Removal