56-25

SRS DTC Troubleshooting: 56-25

DTC 56-25:

Lost Communication With the Gauge Control Module

NOTE:

- Before doing this troubleshooting procedure, review SRS Precautions and Procedures Service and Repair, General Troubleshooting Information Reading and Clearing Diagnostic Trouble Codes, and Battery Terminal Disconnection and Reconnection Procedures.
- Check for any F-CAN and B-CAN communication DTCs, and troubleshoot those DTCs before doing this troubleshooting procedure.

1. Release the parking brake, turn the ignition switch to ON (II), and see if the brake system light comes on for 2 seconds and then goes off.

Does the brake system light come on?

YES -

Go to step 2.

NO -

Faulty gauge control module. Do the gauge control module self-diagnostic function Initial Inspection and Diagnostic Overview.�

2. Clear the DTCs with HDS Reading and Clearing Diagnostic Trouble Codes.

3. Turn the ignition switch to ON (II), then wait for 10 seconds.

4. Check for DTCs with the HDS Reading and Clearing Diagnostic Trouble Codes.

Is DTC 56-25 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures Reading and Clearing Diagnostic Trouble Codes. If another DTC is indicated, troubleshoot the DTC.�

5. Turn the ignition switch to LOCK (0).

6. Disconnect the negative cable from the battery, and wait at least 3 minutes.

7. Disconnect SRS unit connector A (28P) from the SRS unit Service and Repair.

8. Disconnect gauge control module 36P connector from the gauge control module Gauge Control Module Replacement.

9. Install a jumper wire between SRS unit connector A (28P) terminals No. 11 and No. 12.






10. Measure the resistance between gauge control module 36P connector terminals No. 33 and No. 34. There should be less than 1.0 Ohms.





Is the resistance as specified?

YES -

Faulty SRS unit or poor connection at SRS unit connector A (28P) and the SRS unit. Check the connection between the connector and the SRS unit. If the connection is OK, replace the SRS unit SRS Unit Replacement.�

NO -

Open in the harness between SRS unit connector A (28P) terminal No. 11 and gauge control module 36P connector terminal No. 34, and between SRS unit connector A (28P) terminal No. 12 and gauge control module 36P connector terminal No. 33; replace the faulty harness, then clear the DTC.�