DTC P0601 or P1790 Non European or N. American Emissions
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0601 or P1790 System Voltage Low
Conditions for Setting the DTC
The transmission control module (TCM) detects a difference between the calculated checksum data and the rear checksum data.
Action Taken When the DTC Sets
The TCM will request the illumination of the hold lamp and store the DTC when the TCM detects a failure on the first ignition cycle.
Conditions for Clearing the DTC
| • | 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. |
Cause of Failure
| • | 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 | Select the DTC Information menu. Is DTC P1790 displayed? | Go to Step 5 | Go to Step 4 |
4 | Repair the temporary connection failure of the connector. Refer to Wiring Harness and Connector Inspection Diagnosis . Did you complete the repair? | System OK | -- |
5 | Replace the transmission control module (TCM). Refer to Transmission Control Module Replacement . Did you complete the replacement? | System OK | -- |
DTC P0601 or P1790 European and N. American Emissions
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC P0601 or P1790 Control Module Read Only Memory (ROM) |
| • | DTC P1790 2nd Break Control Solenoid |
Conditions for Setting the DTC
The transmission control module (TCM) detects a difference between the calculated checksum data and the rear checksum data.
Action Taken When the DTC Sets
The TCM will request the illumination of the malfunction indicator lamp (MIL) and store the DTC when the TCM detects a failure on the first ignition cycle.
Conditions for Clearing the DTC
| • | 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. |
Cause of Failure
| • | 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 | Select the DTC Information menu. Is DTC P1790 displayed? | Go to Step 5 | Go to Step 4 |
4 | Repair the temporary connection failure of the connector. Refer to Wiring Harness and Connector Inspection Diagnosis . Did you complete the repair? | System OK | -- |
5 | Replace the transmission control module (TCM). Refer to Transmission Control Module Replacement . Did you complete the replacement? | System OK | -- |
