DTC U0155-00: Lost Communication With the Gauge Control Module (SRS Unit) (2014-15)

NOTE: 

• Before doing this troubleshooting procedure, find out if the vehicle was in a collision. If so, verify that all the required components were replaced with new components of the correct part number and were properly installed. Refer to: SRS Component Replacement/Inspection After Deployment
• Before doing this troubleshooting procedure, review SRS Precautions and Procedures , General Troubleshooting Information , and 12 Volt Battery Terminal Disconnection and Reconnection .
• Before replacing the SRS unit, check the SRS unit software version with the HDS. If the software version is not the latest, update the SRS unit software , and retest.

DTC (SRS)

1. CAN gateway DTC check

   -1. Turn the vehicle to the ON mode.

   - 2. Check for CAN gateway DTC with the HDS.

   DTC Description	DTC
   U0029-00 CAN Gateway F-CAN ch A Bus Off
   U0047-00 CAN Gateway F-CAN ch B Bus Off
   U0056-00 CAN Gateway F-CAN ch C Bus Off
   U3000-49 CAN Gateway Internal Failure

   DTC (CAN gateway)

   Is DTC U0029-00, U0047-00, U0056-00 and/or U3000-49 indicated?

   YES 

   Go to the indicated DTC's troubleshooting.

   NO 

   Go to step 2.

2. F-CAN circuit communication check

   -1. Select the FUNCTION TEST in the CAN gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

   Which result is indicated?

   Gauge control module (Bus A) is Not Available

   Go to step 3.

   SRS unit (Bus C) is Not Available

   Go to step 4.

   Gauge control module and SRS unit are Detect

   Intermittent failure, the system is OK at this time.

3. Open wire check (F-CAN A_L, F-CAN A_H lines)

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

   - 2. Disconnect the following connectors:

   CAN gateway 24P connector - Refer to: CAN Gateway Removal and Installation (2014-15)

   Gauge control module connector A (32P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	CAN gateway 24P connector: disconnected
   	Gauge control module connector A (32P): disconnected
   Test circuit	F-CAN A_L
   Test point 1	CAN gateway 24P connector No. 15 (RED)
   Test point 2	Gauge control module connector A (32P) No. 20 (RED)

   Test circuit	F-CAN A_H
   Test point 1	CAN gateway 24P connector No. 14 (WHT)
   Test point 2	Gauge control module connector A (32P) No. 19 (WHT)

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

   Is there continuity?

   YES 

   The F-CAN A_L and F-CAN A_H wires are OK. Check for poor connections or loose terminals at the CAN gateway and the gauge control module, and recheck. If the DTC is still indicated, replace the gauge control module .

   NO 

   Repair an open in F-CAN A_L or F-CAN A_H wire between the CAN gateway and the gauge control module.

4. Open wire check (F-CAN C_L, F-CAN C_H lines)

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

   - 2. Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.

   - 3. Disconnect the following connectors:

   CAN gateway 24P connector - Refer to: CAN Gateway Removal and Installation (2014-15)

   SRS unit connector A (39P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	CAN gateway 24P connector: disconnected
   	SRS unit connector A (39P): disconnected
   Test circuit	F-CAN C_L
   Test point 1	CAN gateway 24P connector No. 8
   Test point 2	SRS unit connector A (39P) No. 21

   Test circuit	F-CAN C_H
   Test point 1	CAN gateway 24P connector No. 9
   Test point 2	SRS unit connector A (39P) No. 20

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

   Is there continuity?

   YES 

   The F-CAN C_L and F-CAN C_H wires are OK. Check for poor connections or loose terminals at the CAN gateway and the SRS unit, and recheck. If the DTC U0155-00 is still indicated, replace the SRS unit .

   NO 

   Repair an open in F-CAN C_L or F-CAN C_H wire between the CAN gateway and the SRS unit.