This diagnostic procedure supports the following DTC:
DTC P0604 Control Module Random Access Memory (RAM)
• | The transmission control module (TCM) cannot carry out the 4 random access memory (RAM) initialization routines. |
• | The TCM detects that the RAM cannot be written and read correctly. |
The TCM will request the illumination of the hold lamp and store the DTC when the TCM detects failures on 2 consecutive ignition cycles.
• | The TCM turns OFF the hold lamp when no further failures are detected on the next ignition cycles. |
• | The scan tool can clear the DTC from the TCM history. |
• | The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault. |
• | The harness or connector between the TCM and the engine control module (ECM) |
• | The ECM |
• | The TCM |
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check - Automatic Transmission? | Go to Step 2 | |
2 |
Is the hold lamp ON? | Go to Step 3 | Go to Step 4 |
3 |
Is DTC P0604 displayed? | Go to Step 5 | Go to Step 4 |
4 | Inspect the transmission control module (TCM) wiring harness and connector for signs of an intermittent condition. Repair as necessary. Did you complete the action? | System OK | -- |
5 | Replace the TCM. Refer to Transmission Control Module Replacement . Did you complete the replacement? | System OK | -- |
This diagnostic procedure supports the following DTC:
DTC P0604 Control Module Random Access Memory (RAM)
• | The transmission control module (TCM) cannot carry out the 4 random access memory (RAM) initialization routines. |
• | The TCM detects that the RAM cannot be written and read correctly. |
The TCM will request the illumination of the malfunction indicator lamp (MIL) and store the DTC when the TCM detects failures on 2 consecutive ignition cycles.
• | The TCM turns off the MIL when no further failures are detected on the next ignition cycles. |
• | The scan tool can clear the DTC from the TCM history. |
• | The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault. |
• | The harness or connector between the TCM and the engine control module (ECM) |
• | The ECM |
• | The TCM |
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check - Automatic Transmission? | Go to Step 2 | |
2 |
Is the malfunction indicator lamp (MIL) ON? | Go to Step 3 | Go to Step 4 |
3 |
Is DTC P0604 displayed? | Go to Step 5 | Go to Step 4 |
4 | Inspect the transmission control module (TCM) wiring harness and connector for signs of an intermittent condition. Repair as necessary. Did you complete the action? | System OK | -- |
5 | Replace the TCM. Refer to Transmission Control Module Replacement . Did you complete the replacement? | System OK | -- |