Operation CHARM: Car repair manuals for everyone.

DTC 51 After Air Bag Deployment

NOTE: Air bag diagnostic monitors can withstand several air bag deployments and do not need to be replaced after every deployment. Only replace the air bag diagnostic monitor if it is damaged.

Occasionally, after an air bag deploys, the internal wiring of the air bag(s) may become shorted to the metal housings of the air bag(s). This internal air bag short is detected by the air bag diagnostic monitor as short to ground in the air bag deployment wiring. Since the air bag diagnostic monitor is still operating immediately after most deployments, the air bag diagnostic monitor will detect the shorted wiring and will flash DTC 13 or 14 and open the internal thermal fuse. After the deployment, as the air bag(s) cool off, the internal shorted wiring may correct itself. The short to ground will no longer exist and the air bag diagnostic monitor will flash Diagnostic Trouble Code (DTC) 51. If a vehicle with a deployed air bag is flashing DTC 51, inspect and replace all the damaged areas of the vehicle that have crushed wiring, sensors, etc. If no damage is found, assume that the deployed air bag was the cause for the intermittent short and replace the air bag diagnostic monitor when the new air bag module(s) are installed.

After a short to ground has been corrected, the air bag diagnostic monitor will flash out DTC 51. DTC 51 indicates that the thermal fuse inside the air bag diagnostic monitor is open and the short to ground no longer exists.

If a short to ground has not been located and serviced (short to ground corrected itself), consult OASIS for potential wiring shorts.

If a short to ground has been correctly located and serviced, replace the air bag diagnostic monitor. DO NOT replace the air bag diagnostic monitor until the short to ground has been positively located and serviced. Replacing the air bag diagnostic monitor before servicing a short to ground will result in repeat service.