DTC U0155-00 (2014 2015 SRS Unit)

DTC U0155-00  : Lost Communication With the Gauge Control Module

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 that they were properly installed .
• Before doing this troubleshooting procedure, review SRS Precautions and Procedures , General Troubleshooting Information , and Battery Terminal Disconnection and Reconnection - Refer to: Battery Terminal Disconnection and Reconnection (2016), .
• 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. Body electrical system check

   -1. Check for any F-CAN and B-CAN communication DTCs with the HDS.

   DTC Description	DTC

   Are there any communication DTCs?

   YES 

   Go to the appropriate DTC troubleshooting.

   NO 

   Go to step 2.

2. Brake system indicator check

   -1. Release the parking brake, turn the vehicle to the OFF (LOCK) mode, and see if the brake system indicator comes on for 2 seconds and then goes off.

   Does the brake system indicator come on and then go off after 2 second?

   YES 

   Go to step 3.

   NO 

   Do the gauge control module self-diagnostic function - Refer to: Gauges Self-Diagnostic Function (2014 2015), . If gauge control module has the problem, replace the gauge control module , then clear the DTC, and retest. If the DTC is still present, replace the SRS unit - Refer to: or SRS Unit Removal and Installation .

3. DTC check

   -1. Clear the DTCs with the HDS.

   - 2. Turn the vehicle to the ON mode, then wait for 10 seconds.

   - 3. Check for DTCs with the HDS.

   DTC Description	DTC
   U0155-00 Lost communication with the gauge control module

   Is DTC U0155-00 indicated?

   YES 

   Go to step 4.

   NO 

   Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures . If another DTC is indicated, troubleshoot the DTC.

4. Open wire check (F-CAN_H, F-CAN_L lines)

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

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

   - 3. Disconnect the following connectors.

   SRS unit connector A (39P) - Refer to: SRS Unit Removal and Installation

   Gauge control module connector A (32P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	SRS unit connector A (39P): disconnected
   	Gauge control module connector A (32P): disconnected
   Test circuit	F-CAN_H
   Test point 1	SRS unit connector A (39P) No. 20
   Test point 2	Gauge control module connector A (32P) No. 27 (WHT)

   Test circuit	F-CAN_L
   Test point 1	SRS unit connector A (39P) No. 21
   Test point 2	Gauge control module connector A (32P) No. 28 (BLK)

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

   Is there continuity?

   YES 

   The F-CAN_H and F-CAN_L wires are OK. Faulty SRS unit or poor connection at SRS unit connector A (39P) and the SRS unit. Check the connection; if the connection is OK, replace the SRS unit - Refer to: SRS Unit Removal and Installation, . If the DTC does not clear, replace the dashboard wire harness.

   NO 

   Open in the harness between SRS unit connector A (39P) terminal No. 20 and gauge control module connector A (32P) terminal No. 27, or between SRS unit connector A (39P) terminal No. 21 and gauge control module connector A (32P) terminal No. 28; replace the dashboard wire harness, then clear the DTC.