DTC U1101 (2016 2017 2018 PGM-FI System) (Without CAN Gateway)

DTC U1101  : F-CAN Malfunction (PCM-ACM)

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
   U1101 F-CAN Malfunction (PCM-ACM)

   Is DTC U1101 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 engine mount 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. ACM system check

   -1. Check for ACM DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   P15AB Engine Mount Control Unit Power Source Circuit Low Voltage

   Is DTC P15AB indicated?

   YES 

   Go to the troubleshooting for DTC P15AB .

   NO 

   Go to step 3.

3. Open wire check (F-CAN A_H line)

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

   - 2. Jump the SCS line with the HDS.

   - 3. Disconnect the following connectors.

   PCM connector A (51P)

   Engine mount control unit 16P connector

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (51P): disconnected
   	Engine mount control unit 16P connector: disconnected
   Test point 1	Engine mount control unit 16P connector No. 13
   Test point 2	PCM connector A (51P) No. 9 - Refer to: PCM Connector for Inputs and Outputs (2016), or PCM Connector for Inputs and Outputs (2017 2018 2019 2020)

   Is there continuity?

   YES 

   The F-CAN A_H wire is OK. Go to step 4.

   NO 

   Repair an open in the F-CAN A_H wire between the PCM (A9) and the engine mount control unit.

4. Open wire check (F-CAN A_L line)

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (51P): disconnected
   	Engine mount control unit 16P connector: disconnected
   Test point 1	Engine mount control unit 16P connector No. 15
   Test point 2	PCM connector A (51P) No. 10 - Refer to: PCM Connector for Inputs and Outputs (2016), or PCM Connector for Inputs and Outputs (2017 2018 2019 2020)

   Is there continuity?

   YES 

   The F-CAN A_L wire is OK. Substitute a known-good engine mount control unit , then recheck. If DTC U1101 is not indicated after the engine mount control unit was substituted, replace the original engine mount control unit .

   NO 

   Repair an open in the F-CAN A_L wire between the PCM (A10) and the engine mount control unit.