56-32

SRS DTC Troubleshooting: 56-21, 56-31, 56-22, 56-53, 56-32, 56-33

DTC 56-21, 56-31:

Lost Communication With the PCM (PGM-FI system)

DTC 56-22, 56-23, 56-32, 56-33:

Undefined Data Received From the PCM (PGM-FI system)

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.
- 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 SRS Unit Update, and retest.

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

Are there any communication DTCs?

YES -

Go to the appropriate DTC troubleshooting.�

NO -

Go to step 2.

2. Clear the DTC memory.

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

4. Read the DTC.

Is DTC 56-21, 56-31, 56-22, 56-23, 56-32, or 56-33 indicated?

YES -

Go to step 5.

NO -

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

5. Turn the ignition switch to ON (II), and see if the malfunction indicator lamp (MIL) comes on.

Does the MIL stay on longer than 30 seconds?

YES -

Go to the MIL Circuit Troubleshooting MIL Circuit Troubleshooting.�

NO -

Go to step 6.

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

7. Jump the SCS line with the HDS.

NOTE: This stop must be done to protect the PCM from damage.

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

9. Disconnect SRS unit connector A (39P) from the SRS unit.

10. Disconnect PCM connector A (49P) from the PCM.

11. Check for continuity between SRS unit connector A (39P) terminals No. 16 and No. 17 and PCM connector A (49P) terminals No. 48 and No. 49.





Is there continuity?

YES -

Faulty SRS unit or poor connection at SRS unit connector A (39P) 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. If the DTC does not clear, replace the harness.�

NO -

Open in the right engine compartment wire harness or the dash board wire harness; replace the faulty harness, then clear the DTC.�