MIL Circuit Troubleshooting

MIL Circuit Troubleshooting 

1. Gauge control module check

   -1. Turn the vehicle to the ON mode.

   -2. Do the gauge self-diagnostic function .

   Does the MIL flash?

   YES 

   Go to step 2.

   NO 

   Substitute a known-good gauge control module , then recheck. If the symptom/indication goes away with a known-good gauge control module, replace the original gauge control module .

2. PCM check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Connect the HDS to the DLC.

   -3. Turn the vehicle to the ON mode.

   -4. Check the parameter (s) below with the HDS.

   Signal	Threshold		Current conditions
   	Values	Unit	Values	Unit
   SCS	Short

   Do the current condition (s) match the threshold?

   YES 

   Go to step 3.

   NO 

   Update the PCM  if it does not have the latest software, or substitute a known-good PCM , then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM .

3. Shorted wire check (SCS line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Jump the SCS line with the HDS.

   -3. Disconnect the following connector.

   PCM connector A (51P)

   -4. Disconnect the HDS.

   -5. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (51P): disconnected
   Test point 1	PCM connector A (51P) No. 44
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short in the SCS wire between the PCM (A44) and the DLC.

   NO 

   The SCS wire is OK. Update the PCM  if it does not have the latest software, or substitute a known-good PCM , then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM .