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DTC Troubleshooting




Control System DTCs

DTC Troubleshooting: P0103

DTC P0103 : MAF Sensor Circuit High Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How to Troubleshoot the Fuel And Emissions Systems.


1. Problem verification:

-1. Turn the ignition switch to ON (II), and wait 2 seconds.

-2. Check the parameter(s) below with the HDS.






Do the current condition(s) match the threshold?
-YES- The failure is duplicated. Go to step 2.
-NO- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the PCM.

2. Open wire check (VGM line):

-1. Turn the ignition switch to LOCK (0).

-2. Jump the SCS line with the HDS.

-3. Disconnect the following connectors.






-4. Check for continuity between test points 1 and 2.










Is there continuity?
-YES- The VGM wire is OK. Go to step 3.
-NO- Repair an open in the VGM wire between the PCM (B43) and the MAF sensor/IAT sensor, then do the repair verification.

3. PCM internal circuit check:

-1. Reconnect the following connector.






-2. Connect terminals A and B with a jumper wire.










-3. Turn the ignition switch to ON (II).

-4. Clear the DTC with the HDS. How to Troubleshoot the Fuel And Emissions Systems

-5. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0103 indicated?
-YES- Update the PCM PCM Update if it does not have the latest software, or substitute a known-good PCM Service and Repair, then do the repair verification.
-NO- The PCM internal circuit is OK. Replace the MAF sensor/IAT sensor Service and Repair, then do the repair verification.

Repair verification:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect all connectors.

-3. Turn the ignition switch to ON (II).

-4. Reset the PCM with the HDS How to Troubleshoot the Fuel And Emissions Systems.

-5. Do the PCM idle learn procedure PCM Idle Learn Procedure.

-6. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0103 indicated?
-YES- Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the PCM. If the PCM was updated, substitute a known-good PCM Service and Repair, then recheck. If the PCM was substituted, go to step 1.
-NO- Troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.