P1530

Wiring Diagram:

Circuit Description
The test switch terminal is located in the duty check data link connector. The PCM fixes the ignition timing to the base setting when the test switch terminal is grounded.

Conditions for Setting the DTC
^ Vehicle speed greater than 32 km/h (20 mph).
^ The test switch is ON (circuit is grounded).
^ The condition is present for 5 seconds

Action Taken When the DTC Sets
^ The Malfunction Indicator Lamp (MIL) will illuminate.
^ The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame buffer.

Conditions for Clearing the MIL/DTC
^ The MIL turns OFF after three consecutively passing trips without a fault present.
^ A History DTC clears after 40 consecutive warm-up cycles without a fault.
^ Use the scan tool Clear DTC Information function or disconnect the PCM battery feed in order to clear the DTC.

Diagnostic Aids
Check for a damaged wiring harness. Inspect the wiring harness for damage that may cause a short to ground. Wiggle the wiring harness to the duty check data link connector while the engine running. Monitor the Spark Advance Adjust Test Switch parameter on the scan tool for an ON display indicating that the harness is shorting to ground.

Test Description
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 fault is present.
3. This step checks for a short to ground on the test switch terminal and its circuitry. A short to ground causes the ignition timing will be fixed at the base setting.