P0604

4GR-FSE 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 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

1. Connect the Techstream to the DLC3.

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

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

4. Turn the Techstream off.

5. Turn the engine switch off.

6. Disconnect the Techstream.

7. Disconnect the cable from the negative (-) battery terminal and wait for 1 minute.

8. Connect the cable to the negative (-) battery terminal.

9. Connect the Techstream to the DLC3.

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

11. Wait 16 seconds or more.

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

13. Read the pending DTCs.

HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.

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

15. Input the DTC: P0604.

16. Check the DTC judgment result.





HINT
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.

17. If the judgment result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

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

INSPECTION PROCEDURE

HINT
Read freeze frame data using Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction Freeze Frame Data.

PROCEDURE

1. READ OUTPUT DTC (DTC P0604)

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(e) Turn the Techstream off.

(f) Turn the engine switch off.

(g) Disconnect the Techstream.

(h) Disconnect the cable from the negative (-) battery terminal and wait for 1 minute.

(i) Connect the cable to the negative (-) battery terminal.

(j) Connect the Techstream to the DLC3.

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

(l) Turn the Techstream on.

(m) Wait for 16 seconds.

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

(o) Read the DTCs.

Result:





B -- REPLACE ECM Removal

A -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems