Sorry it's taken so long to reply...Things have gotten busy with school this past week. Airbag light is definitely flashing 5+1. Yep... leave it to me to get the problem that doesn't exist! Besides the light, are there other methods for checking codes with the airbag module?

 

if you are handy with electronics and a soldering iron, replace the fault fuse on the SRS controller circuit board or buy a rebuilt unit
third option, local junke yard

Fault Code 51
Diagnostic Monitor Internal Thermal Fuse Blown and Short to Ground No Longer Exists (Short to Ground was Repaired or is Intermittent)


Circuit Description


Normal Operation

NOTE:
The diagnostic monitor contains an internal thermal fuse that is not serviceable. The thermal fuse is controlled by a computer inside the diagnostic monitor. The computer will blow the thermal fuse whenever a short on the deployment circuits occurs. The thermal fuse does not blow because of excessive current flowing through it. DO NOT attempt to jumper out the thermal fuse with a circuit breaker or any other type of fuse.

NOTE:
DO NOT install a new diagnostic monitor until the short has been located and corrected. If a short to ground has not been located and corrected, then the short to ground is intermittent and IS NOT PRESENT AT THIS TIME. Installing a new diagnostic monitor with an intermittent short in the system will result in blown diagnostic monitors and repeat repairs.

The diagnostic monitor measures the voltages at the diagnostic monitor connector pins. When certain air bag deployment wires are shorted to ground (heavy lines illustrated in the schematic below), the system may become susceptible to unwanted deployment of the air bag(s). The diagnostic monitor senses a short to ground on any of these circuits and helps prevent unwanted air bag deployant by blowing the diagnostic monitor thermal fuse. Blowing this fuse removes all power (battery and back-up power) from the air bag deployment circuits. While the short to ground exists, the monitor will flash fault code 13. If the short to ground is intermittent and temporarily corrects itself, the diagnostic monitor will flash code 51.

NOTE:
If the short to ground returns, the high priority code 13 will flash instead of 51.

If the air bag lamp is flashing code 51 and a short to ground has not been serviced, this means that an intermittent short to ground exists in the air bag system. The diagnostic monitor should be replaced only after repairs to the intermittent short have been completed.

Some service tips for finding an intermittent short to ground are:

1. Consult OASIS (Restraint Systems Service Code 104000) for up-to-date diagnostics and descriptions of wiring concern locations for the vehicle (VIN number) you are working on. OASIS is updated daily using concern descriptions from engineering and Dealership Service sources.

2. Inspect wiring and harness in areas where they pass through or are located next to metal components (i.e., engine compartment bulkhead, body sheet metal, component mounting brackets, etc).


Code 51 After Air Bag Deployment

Occasionally, immediately after an air bag deploys, the internal wiring of the air bag may become shorted to the metal housing of the air bag. This internal air bag short is detected by the diagnostic monitor as short to ground in the air bag deployment wiring. Since the diagnostic monitor is still operating immediately after most deployments, the monitor will detect the shorted wiring and will flash code 13 and blow the internal thermal fuse. After the deployment, as the air bag cools off, the internal shorted wiring may correct itself, therefore the short to ground will no longer exist and the diagnostic monitor will flash code 51. If a vehicle with a deployed air bag is flashing code 51, inspect and replace all the damaged areas of the vehicle with 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 diagnostic monitor when the new air bag is installed.

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


Code 51 Wiring Schematic

 

Thanks, 96! Much appreciated! Any chance of posting the actual schematics of this circuit?

 

Cooper had a nice post in this thread about where the thermal fuse was in the airbag module.

https://www.ford-trucks.com/forums/5...irbag+computer

I know there is another thread here somewhere with pictures but I can't seem to find it.

Man I can still hear the ringing from my ears when both went off in one of my Accords . I can't imagine one going off out of the blue.

Hi honey I got into an accident and hit a ghost there was no damage to the van but the airbag went off .

 

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Why is this up? Its old, does someone need answers about a 51 airbag code? Fuse on the board. The DREADED 51 !! aaahhhhhhhhhh!!!!!!!!!