DTC U0100, U0122 (Keyless Access Power Control Unit (With CAN Gateway)) (2019)

DTC U0100  : Power control unit lost communication with PCM

DTC U0122  : Power control unit lost communication with VSA modulator-control unit (VSA message)

NOTE: 

• Refer to the DTC code shown on the display, and then inspect the connectors and terminals based on the instructions in the table below.
• The DTC may be stored due to the grounding failure or the power source failure at the transmitting control unit (the grounding inspection and the power source inspection on each control unit are required prior to this checking process).

DTC (Power Control Unit)

NOTE: 

• If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
• If you have any loss of communication DTCs for the PCM, troubleshoot those DTCs first.

1. Problem verification

   -1. Clear the DTCs with the HDS.

   Clear DTCs

   -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   -3. Wait for at least 6 seconds.

   -4. Check for DTCs with the HDS.

   DTC Description	DTC
   U0100 Power control unit lost communication with PCM
   U0122 Power control unit lost communication with VSA modulator-control unit (VSA message)

   Are DTC U0100 or U0122 indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for loose or poor connections.

2. CAN gateway system DTC check

   -1. Check for CAN gateway system DTCs with the HDS.

   DTC Description	DTC
   U0029-00 CAN Gateway F-CAN ch A Bus Off
   U3000-49 CAN Gateway Internal Failure

   Is DTC U0029-00 and/or U3000-49 indicated?

   YES 

   Go to the troubleshooting for CAN gateway system DTC(s) .

   NO 

   Go to step 3.

3. Open wire check (F-CAN_L, F-CAN_H lines) (between the receiving control unit and the CAN gateway)

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

   -2. Disconnect the following connectors.

   CAN gateway 16P connector Keyless access/TPMS control unit connector C (20P)

   -3. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode CAN gateway 16P connector: disconnected Keyless access/TPMS control unit connector C (20P): disconnected
   Test point 1	CAN gateway 16P connector (female terminals) No. 3:
   Test point 2	Keyless access/TPMS control unit connector C (20P) No. 2

   Test point 1

   CAN gateway 16P connector (female terminals) No. 11:

   Test point 2

   Keyless access/TPMS control unit connector C (20P) No. 12

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

   Is there continuity?

   YES 

   Go to step 4.

   NO 

   Repair an open or high resistance in the wire(s).

4. Open wire check (F-CAN_H, F-CAN_L lines) (between the transmitting control unit and the CAN gateway)

   -1. Jump the SCS line with the HDS, and wait more than 1 minute.

   SCS short

   -2. Disconnect the transmitting control unit connectors.

   (Refer to the DTC code shown on the display, and then disconnect the connector(s) based on the instructions in the chart below.)

   PCM connector A (51P)

   VSA modulator-control unit 38P connector

   -3. Check for continuity between the receiving control unit and the transmitting control unit on the F-CAN_H circuit and the F-CAN_L circuit as specified in the table while in the vehicle OFF (LOCK) mode.

   DTC	CIRCUIT NAME	RECEIVING CONTROL UNIT	TRANSMITTING CONTROL UNIT
   U0100	F-CAN_H	CAN gateway 16P connector (female terminals) No. 3:	PCM connector A (51P) No. 9
   	F-CAN_L	CAN gateway 16P connector (female terminals) No. 11:	PCM connector A (51P) No. 10
   U0122	F-CAN_H	CAN gateway 16P connector (female terminals) No. 3:	VSA modulator-control unit 38P connector No. 6
   	F-CAN_L	CAN gateway 16P connector (female terminals) No. 11:	VSA modulator-control unit 38P connector No. 7

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

   Is there continuity?

   YES 

   The F-CAN_L and F-CAN_H wires are OK. Go to step 5.

   NO 

   Repair an open or high resistance in the wire(s).

5. Determine possible failure area (the receiving control unit or the transmitting control unit)

   -1. Reconnect all connectors.

   -2. Clear the DTCs with the HDS.

   Clear DTCs

   -3. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   -4. Wait for at least 6 seconds.

   -5. Check for DTCs with the HDS.

   DTC Description	DTC
   U0100 Power control unit lost communication with PCM
   U0122 Power control unit lost communication with VSA modulator-control unit (VSA message)

   Are DTC U0100 and U0122 indicated?

   YES 

   Check for loose terminals and poor connections in the keyless access/TPMS control unit connector. Check is OK, replace the keyless access/TPMS control unit .

   NO 

   The keyless access/TPMS control unit is OK at this time. Replace the transmitting control unit.

   (Refer to the DTC code shown on the display, and then replace the control unit based on the instructions in the chart below.)

   DTC	TRANSMITTING CONTROL UNIT
   U0100	Replace the PCM
   U0122	Replace the VSA modulator-control unit