Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC P0601: Control Module Read Only Memory (ROM)DTC P0602: Control Module Not Programmed
DTC P0603: Control Module Long Term Memory Reset
DTC P0604: Control Module Random Access Memory (RAM)
DTC P0606: Control Module Internal Performance
Circuit/System Description
This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). This diagnostic also addresses if the ECM is not programmed.
Conditions for Running the DTC
P0601
The checksum calculation at power down in the last drive cycle was completely finished. DTC P0601 runs continuously for approximately 30 seconds, at ignition OFF.
P0602
The ignition is ON, with the engine OFF. DTC P0602 runs continuously when the ignition is ON for greater than 1 second.
P0603
| • | The ignition is ON. |
| • | The power down calculation in the last drive cycle was completely finished. |
| • | DTC P0603 runs continuously once the conditions above have been met for greater than 5 seconds. |
P0604
The read/write test at power down in the last drive cycle completely finished. DTC P0604 runs continuously for approximately 5 seconds, at ignition OFF.
P0606
DTC P0606 runs continuously with ignition ON or engine operating.
Conditions for Setting the DTC
P0601
The ECM detects the incorrect read only memory (ROM) checksum for greater than 4 seconds.
P0602
The ECM detects that programming is incomplete for greater than 4 seconds.
P0603
The ECM detects an error during the shut down path test for 4 seconds, or a cumulative of 50 seconds.
P0604
The ECM detects random access memory (RAM) errors for greater than 4 seconds.
P0606
The ECM detects an internal condition for greater than 4 seconds, or a cumulative of 50 seconds.
Action Taken When the DTC Sets
DTCs P0601, P0602, P0604, and P0606 are Type A DTCs.
Conditions for Clearing the DTC
DTCs P0601, P0602, P0604, and P0606 are Type A DTCs.
Reference Information
Description and Operation
Engine Control Module Description
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Circuit/System Verification
- Ignition ON, observe the scan tool DTC information. DTC P0602 or P0606 should not set.
- Observe the scan tool DTC information. DTC P0601, P0603, or P0604 should not set.
- Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.
| ⇒ | If DTC P0602 failed this ignition, program the ECM. If the DTC resets, replace the ECM. |
| ⇒ | If DTC P0606 failed this ignition, clear the DTCs with a scan tool and verify the DTC does not reset. If the DTC resets, replace the ECM. |
| ⇒ | If a DTC failed this ignition, replace the ECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for engine control module replacement, setup, and programming
