DTC U129E (2014 2015 PGM-FI System)

DTC U129E  : F-CAN Malfunction (PCM-Power Control Unit (PCU))

DTC (PGM-FI)

1. DTC check

   -1. Turn the vehicle to the ON mode.

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

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   U0029 F-CAN Malfunction (BUS-OFF (PCM))
   U129E F-CAN Malfunction (PCM-Power Control Unit (PCU))

   Are DTC U0029 and U129E indicated at the same time?

   YES 

   Do the troubleshooting for DTC U0029 - Refer to: DTC Troubleshooting: U0029(PGM-FI System),  or DTC U0029(PGM-FI System (With CAN Gateway)) (2016) .

   NO 

   Go to step 2.

2. Problem verification

   -1. Clear the DTC with the HDS.

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

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   U129E F-CAN Malfunction (PCM-Power Control Unit (PCU))

   Is DTC U129E indicated?

   YES 

   The failure is duplicated. Go to step 3.

   NO 

   Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the keyless access/TPMS 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.

3. Keyless access system check

   -1. Check for communication to the keyless access system with the HDS.

   Does the HDS communicate with the keyless access/TPMS control unit?

   YES 

   Go to step 4.

   NO 

   Refer to the appropriate procedure in Symptom Troubleshooting Index for Viewer .

4. Open wire check (F-CAN_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) - Refer to: How to Troubleshoot the A/T System (2014 2015), or How to Troubleshoot the Fuel and Emissions Systems,

   Keyless access/TPMS control unit connector C (20P)

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

   Test condition	OFF mode
   	PCM connector A (51P): disconnected
   	Keyless access/TPMS control unit connector C (20P): disconnected
   Test circuit	F-CAN_H
   Test point 1	Keyless access/TPMS control unit connector C (20P) No. 2 (WHT)
   Test point 2	PCM connector A (51P) No. 9 (WHT)

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The F-CAN_H wire is OK. Go to step 5.

   NO 

   Repair an open in the F-CAN_H wire between the PCM (A9) and the keyless access/TPMS control unit.

5. Open wire check (F-CAN_L line)

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

   Test condition	OFF mode
   	PCM connector A (51P): disconnected
   	Keyless access/TPMS control unit connector C (20P): disconnected
   Test circuit	F-CAN_L
   Test point 1	Keyless access/TPMS control unit connector C (20P) No. 12 (BLK)
   Test point 2	PCM connector A (51P) No. 10 (BLK)

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The F-CAN_L wire is OK. Substitute a known-good keyless access/TPMS control unit , then recheck. If DTC U129E is not indicated after substitution, replace the original keyless access/TPMS control unit .

   NO 

   Repair an open in the F-CAN_L wire between the PCM (A10) and the keyless access/TPMS control unit.