Is there continuity?
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 See: Relays and Modules/Relays and Modules - Restraints and Safety Systems/Air Bag Control
Module/Service and Repair/SRS Unit Replacement.?
Open in the right engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.?
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)
- Before doing this troubleshooting procedure, review SRS Precautions and Procedures See: Body and Frame/Air Bag(s) Arming and
Disarming/Service and Repair, General Troubleshooting Information See: Restraints and Safety Systems/Air Bag Systems/Testing and
Inspection/Reading and Clearing Diagnostic Trouble Codes, and Battery Terminal Disconnection and Reconnection See: Starting and
Charging/Battery/Service and Repair/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 See: Restraints and Safety Systems/Air Bag Systems/Testing and Inspection/Programming and Relearning/SRS Unit Update,
1. Check for any F-CAN and B-CAN communication DTCs with the HDS.
Are there any communication DTCs?
Go to the appropriate DTC troubleshooting.?