DTC U0131: F-CAN Malfunction (PCM-EPS Control Unit)

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: HOW TO TROUBLESHOOT THE FUEL AND EMISSIONS SYSTEMS or How to Troubleshoot the CVT System(CVT) .

DTC (PGM-FI)

1. Problem verification:

   - 1. Turn the vehicle to the ON mode.

   - 2. Clear the DTC with the HDS.

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

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   U0131 F-CAN Malfunction (PCM-EPS Control Unit)

   Is DTC U0131 indicated?

   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 EPS control unit and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

2. EPS system check:

   - 1. Check that the HDS communicates with the EPS system.

   Does the HDS communicate with the EPS system?

   YES 

   Go to step 3.

   NO 

   Go to the symptom troubleshooting for an EPS indicator does not go off, and no DTCs are stored - Refer to: EPS Symptom Troubleshooting - EPS indicator does not go off, or EPS Symptom Troubleshooting - Steering pull(KA/KC models) .

3. Open wire check (F-CAN_H line):

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

   - 2. Jump the SCS line with the HDS.

   SCS Short

   - 3. Disconnect the following connectors.

   PCM connector A (51P)

   EPS control unit connector B (6P) or B (5P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (51P): disconnected
   	EPS control unit connector B (6P) or B (5P): disconnected
   Test point 1	EPS control unit connector B (6P) No. 4 (USA and Canada models)
   	EPS control unit connector B (5P) No. 1 (Mexico models)
   Test point 2	PCM connector A (51P) No. 2

   Is there continuity?

   YES 

   The F-CAN_H wire is OK. Go to step 4.

   NO 

   Repair an open in the F-CAN_H wire between the PCM (A2) and the EPS control unit.

4. Open wire check (F-CAN_L line):

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (51P): disconnected
   	EPS control unit connector B (6P) or B (5P): disconnected
   Test point 1	EPS control unit connector B (6P) No. 3 (USA and Canada models)
   	EPS control unit connector B (5P) No. 3 (Mexico models)
   Test point 2	PCM connector A (51P) No. 1

   Is there continuity?

   YES 

   The F-CAN_L wire is OK. Update the EPS control unit if it does not have the latest software, or substitute a known-good EPS control unit , then recheck. If DTC U0131 is not indicated after substitution, replace the original EPS control unit .

   NO 

   Repair an open in the F-CAN_L wire between the PCM (A1) and the EPS control unit.