A normal function of the transmission control module (TCM) programming is to perform an internal check that verifies the integrity of the random access memory (RAM) memory allocations.
The DTC P0604 sets when the RAM is not operating correctly when checked on initialization. An area of RAM is failed a read/write test.
• | An area of RAM has failed a read/write test. |
• | System voltage is too high or too low. |
• | Transaxle input voltage is too high or too low. |
• | Immediately after the above condition occurs |
• | The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer. |
• | Adopt Emergency/ Substitute mode and constant 4th gear by hydraulic control. |
• | After ignition OFF/ON : 3rd gear by hydraulic control. Possible P, R and N also possible. |
• | Power supply cut off to the pressure control solenoid (PCS) valve. |
• | The hold lamp will turn OFF when the malfunction has not occurred after 3-ignition cycle. |
• | A history DTC will clear after 40 consecutive warm-up cycles without a fault. |
• | Using a scan tool can clear history DTCs. |
When DTC P0604 sets, the replacement of TCM is recommended.
Step | Action | Yes | No |
---|---|---|---|
1 | Perform the Diagnostic System Check. Is the check completed? | Go to Step 2 | |
2 |
Does the scan tool display P0604? | Go to Step 3 | Go to Diagnostic Aids |
3 |
Is the replacement complete? | Go to Step 4 | -- |
4 |
Does the scan tool indicate that this diagnostic has run and passed? | Go to Step 5 | Go to Step 2 |
5 | Inspect if any DTCs are set. Are any DTCs displayed that have not been diagnosed? | System OK |
A normal function of the transmission control module (TCM) programming is to perform an internal check that verifies the integrity of the random access memory (RAM) memory allocations.
The DTC P0604 sets when the RAM is not operating correctly when checked on initialization. An area of RAM is failed a read/write test.
• | An area of RAM has failed a read/write test. |
• | System voltage is too high or too low. |
• | Transaxle input voltage is too high or too low. |
• | Immediately after the above condition occurs |
• | The malfunction indicator lamp (MIL) will illuminate. |
• | The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer. |
• | Adopt Emergency/ Substitute mode and constant 4th gear by hydraulic control. |
• | After ignition OFF/ON : 3rd gear by hydraulic control. Possible P, R and N also possible. |
• | Power supply cut off to the pressure control solenoid (PCS) valve. |
• | The MIL will turn OFF when the malfunction has not occurred after 3-ignition cycle. |
• | A history DTC will clear after 40 consecutive warm-up cycles without a fault. |
• | Using a scan tool can clear history DTCs. |
When DTC P0604 sets, the replacement of TCM is recommended.
Step | Action | Yes | No |
---|---|---|---|
1 | Perform the Diagnostic System Check. Is the check completed? | Go to Step 2 | |
2 |
Does the scan tool display P0604? | Go to Step 3 | Go to Diagnostic Aids |
3 |
Is the replacement complete? | Go to Step 4 | -- |
4 |
Does the scan tool indicate that this diagnostic has run and passed? | Go to Step 5 | Go to Step 2 |
5 | Inspect if any DTCs are set. Are any DTCs displayed that have not been diagnosed? | System OK |