Test Description

The numbers below refer to the step numbers on the diagnostic procedures.

1. 2
   
   This step checks whether there is communication between the PCM and a scan tool device. If the PCM is unable to provide serial data to the scan tool, there will be no MIL control.
2. 3
   
   If other Instrument Panel Cluster (IPC) functions are not working correctly check for an open GAUGE fuse or for a lack of power and ground to the IPC.
3. 4
   
   This step checks for an open MIL Control circuit or for an internal PCM failure.
4. 5
   
   An open fuse determines if a voltage is constantly being applied to the control circuit.