Battery voltage is supplied to the powertrain control module (PCM) for the retention of certain long term memory data. Diagnostic trouble codes (DTC) and learned engine control parameters are kept in the PCM memory even when the ignition is Off. A DTC P1510 sets and the PCM long term memory information is lost when the memory power input circuit voltage is interrupted.

The engine is running.

The PCM will indicate a DTC P1510 as long as the ignition is On. As soon as the ignition is turned Off the PCM will lose memory of DTC P1510 and DTC P1510 will not be stored.

Check for an open fuse. Replace any open fuses and retest.

If the DTC P1510 is intermittent, driving the vehicle under the following conditions can verify whether the fault is present. Perform the scan tool Clear DTC Information function. Road test the vehicle while monitoring the DTC P1510 diagnostic on the scan tool under the Not Ran Since Code Cleared selection in the DTC Information menu. If DTC P1510 appears in the Not Ran Since Code Cleared list, the P1510 diagnostic has not yet run. When DTC P1510 does not appear in the Not Ran Since Code Cleared list, the P1510 diagnostic has run. If the MIL is NOT illuminated and there is no Pending DTC Status in DTC Information, the P1510 diagnostic has passed. The DTCs MUST be cleared in order to view the Current Status of the Not Ran Since Code Cleared list. DO NOT forget that the Not Ran Since Code Cleared list only indicates that the test has run, not whether the test passed or failed. The DTC Information screen must be checked for Current or Pending status in order to determine the outcome of the diagnostic test involved.

An intermittent malfunction may be caused by a problem in the memory power input circuit. Inspect the wiring harness and components for any of the following conditions:

The numbers below refer to the step numbers in the diagnostic table.

1. The Powertrain (OBD) System Check prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

2. This step determines if the fault is present.

3. This step checks for voltage at the PCM when the ignition is OFF. The PCM should indicate battery voltage on this terminal under all operating conditions.