Air Bag Diagnostics
#1
Air Bag Diagnostics
I haven't seen much on the forum about diagnosing Air Bag issues with early cars. I think some of the later models have a flash code diagnostic but the early ones have nothing, other than old Jaguar Dealer systems which I think are now rare. I have a VCM/IDS set-up and even that can't read the Air Bag module on my 1995 Daimler Six.
So I have used the various information available in JTIS etc. and produced an Air Bag Diagnostics for Dummies document (attached). It is specifically for early cars but I don't think there is much difference (if any) with later models.
If anyone spots any errors or inconsistencies then I'll be happy to amend appropriately.
I hope it will be of some use to someone in the future. Perhaps it can go in the stickies if deemed worthwhile.
So I have used the various information available in JTIS etc. and produced an Air Bag Diagnostics for Dummies document (attached). It is specifically for early cars but I don't think there is much difference (if any) with later models.
If anyone spots any errors or inconsistencies then I'll be happy to amend appropriately.
I hope it will be of some use to someone in the future. Perhaps it can go in the stickies if deemed worthwhile.
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Terrific write-up Brendan. Thanks! I appreciate the effort it takes to create something like this.
Just what I needed for VDP. Tonight I got as far as checking the fuses! All ok there. My prediction is clockspring fail. We shall see.
This should definitely be included in the quick links sticky.
Just what I needed for VDP. Tonight I got as far as checking the fuses! All ok there. My prediction is clockspring fail. We shall see.
This should definitely be included in the quick links sticky.
#5
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#6
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overtheatlantic (10-10-2016)
#7
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Without me fully digesting Brendan excellent document
The resistors are for testing purposes to not have the test meter have too much current going through the squibs in the airbags themselves from blowing up the charge
The same value may or may not be good for your proposal on the module side of the connector , but as long as the connectors to the airbags are removed they will be safe
Caution must be observed when putting back together that there is not a voltage being delivered to the airbags as a replacement module may be in a firing state
The steering column airbag must match the interior color of the car as it comes as a whole unit with the exterior car horn pad , the interior color code is on the cars data plate
I have the part # for the passenger side and probably the steering side in the garage
The resistors are for testing purposes to not have the test meter have too much current going through the squibs in the airbags themselves from blowing up the charge
The same value may or may not be good for your proposal on the module side of the connector , but as long as the connectors to the airbags are removed they will be safe
Caution must be observed when putting back together that there is not a voltage being delivered to the airbags as a replacement module may be in a firing state
The steering column airbag must match the interior color of the car as it comes as a whole unit with the exterior car horn pad , the interior color code is on the cars data plate
I have the part # for the passenger side and probably the steering side in the garage
#11
Yes that's true. But what I need to check first is if all fuses to the airbag module are intact as my SRS light comes on as soon as ignition is turned on, doesn't go out and back on at all and the "Airbag" message on the dash comes on immediately also and stays on. AND, I don't have any communication with my airbag module with my scan tool. I didn't on my ABS module either but I fixed that by resoldering the positive/negative points where the connector goes and now I can read that module again!
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Parker 7 (10-21-2021)
#12
Not all scan tools can read everything
lucky to get one to read transmission codes
see page 21
X300 1996 LWB.pdf (jagrepair.com)
lucky to get one to read transmission codes
see page 21
X300 1996 LWB.pdf (jagrepair.com)
Last edited by Parker 7; 10-21-2021 at 12:11 PM.
#13
I may just have found how to wire in my front and rear marker lamps/tail lamps.............. I made an extra wire at the power feed to the pilot lamp, left side, which is connected to the marker lamps and tail lamps which all are inoperable right now.... I plan to put that extra wire right at fuse #5 on the left hand forward fusebox as that is the feed for the marker lamps..... will see if I can get the lights to come on with the switch then...... if so BINGO i've solved my lamp problem!!!
I didn't have the fuse location and descriptions as my owner manual is missing!! THANKS!!!!
I didn't have the fuse location and descriptions as my owner manual is missing!! THANKS!!!!
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Parker 7 (10-21-2021)
#15
I don't have any communication with my airbag module with my scan tool
Maybe @motorcarman can confirm what they used at the dealers back in the day.
#17
Wow that is really smoked! That shouldn't happen. The white part at the top is the thermal fuse that blows above a certain temperature (which I don't know), saving everything from frying due to a short circuit somewhere.
So you both will need to do some checking of the sensors and such before you try a new module. This can be done based on Air Bags for Dummies, with a multimeter at the module wire plugs. Heed the warnings! Disconnect the airbags and put 2.5 ohm resistors across the sockets.
In my case the module looked fine although the thermal fuse was blown (open circuit). All other tests I did came up fine, so I put a new module in and all was well.
The Ford module from the same era is used in the Jaguar. It is easier to find. Recommend a new, not used unit. Match the numbers.
5 beeps Airbag warning
So you both will need to do some checking of the sensors and such before you try a new module. This can be done based on Air Bags for Dummies, with a multimeter at the module wire plugs. Heed the warnings! Disconnect the airbags and put 2.5 ohm resistors across the sockets.
In my case the module looked fine although the thermal fuse was blown (open circuit). All other tests I did came up fine, so I put a new module in and all was well.
The Ford module from the same era is used in the Jaguar. It is easier to find. Recommend a new, not used unit. Match the numbers.
5 beeps Airbag warning
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