Ford Airbag Halloween Horror
Robo Tech was recently called to address a 2006 Ford F 150 airbag issue. In 2010 Ford
Motor Company has agreed to recall 1.2 million additional F 150 pickup trucks because of
hundreds of reports that the airbag can suddenly and unexpectedly deploy. The N H T S A has
received 269 reports of random airbag deployments, resulting in 98 injuries. The number of reports
was the most in the last 27 years for airbag problems and led to a thorough investigation.
The reported injuries have ranged from chipped teeth, to fractured arms and severe burns.
There was also one reported accident where the driver jumped out of his moving vehicle
after the airbag randomly deployed because he thought it was on fire. Ford had already
recalled 135,000 F 1 50's for the same issue back in February 2009. The newly expanded
recall now includes the 2004 to 2006 model years, as well as some 2006 Lincoln Mark L
T.
This case was going to be a trial in itself. The customer's complaint was a an S R S or
airbag light on from now and then. But the issue was, why from now and then? On top of
that the customer was a bit afraid due to the news of the Ford airbag recall.
I started my diagnostics by retrieving the airbag codes, but unknown to most folks, Ford
S R S systems can be queried without a scan tool. To retrieve codes, verify the ignition
switch is in the run position (engine does not need to be running). Next, locate the
black R A B S 2 diagnostic connector. The diagnostic connector has two mating halves,
one of which has a black orange wire connected to it. Disconnect the two halves. Attach one
end of a jumper wire to the black with orange stripe wire side of the diagnostic connector.
Momentarily ground the opposite end of the jumper wire by connecting it to a good chassis
ground for 1 to 2 seconds. Grounding this wire should start the lamp flashing. The code
consists of a number of short flashes and ends with a long flash. Count the short flashes
and include the following long flash in the count to obtain the code number.
Solid on is an indicator that the R C M, restraint control module or airbag computer has an error
or is disconnected. Upon retreiving the code, D T C number 19 was aquired, which meant,
driver front airbag circuit fault. I then, to be sure, grabbed my Ford scanner and saw
code B 22 93, which meant the same thing on the O B D 2 side. So, my issue was with the
front driver side airbag. But what exactly? Was it the pyrotechnic or explossive device?
Or was it a wiring issue? Now is when it gets interresting.
Airbag modules, due to their sensitive explossive nature can not be probed with an Ohm meter.
The right procedure is to use substitution resistors and let the S R S module do the
checking. An Ohm meter can definitely be used to check wiring, so long as it doesn't probe
on the involve the airbag device itself.
I removed the airbag module and substituted it with the right resistor meant for this
Ford F 1 50. I erased the codes by following an errasure procedure, and took off for a
road test. I wanted to shake and stress the system. I also made repeated turns to flex
the airbag clockspring wire. While doing one of those turns, the S R S light suddenly came
on again. Well, I was getting close. I went back to the shop, erased codes again, and
proceeded to make repeated turns of the speering wheel while in park. But this time nothing
happened. Was this issue related to a loose wire or a clockspring? After about 30 minutes
of testing, I still had no joy on the S R S ligt. But I suddenly remembered that the
horn had gone off in one of those instances of road testing. Sure enough, I decided to
test the horns and suddenly the S R S light came on. Wow, this was weird, I had never
seen that before. Later on while researching the issue I learned of the Ford recall due
to sudden airbag deployment. This an issue that Ford never wanted to aknowledge, but
it's there.
I decided to remove the airbag clockspring and test it with an Ohm meter. I found defective
wiring and what appeared to be cross feeds between wires. This is a very unussual issue
with airbags, which historically have been very reliable. In this world of modern diagnostics
never assume anything.