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Committed to cutting out the extra length of the loom! In for a penny, in for a pound. The left over coils of wires are the airbag sensors and curtain airbags.


I also ran the loom on the other side of the tunnel to keep some separation just in case it affects the EMI. Now to tidy up all the airbag sensor wiring.


Did some research and the airbag module looks for a resistance to see if the airbags are plugged in or not. This won't stop the Jeep from running, just set off the dash light and a DTC (Data Trouble Code). I need to measure the resistance of the different types of airbags it has in case there is a difference between them. Steering, passenger dash, and two curtain airbags. Later models you need to measure the seat belt pretensioners as well.


I have dual stage bags so have to measure both ports. There is a shorting bar that connects both pins as soon as you unplug it. So you have to isolate the bar to get the correct resistance reading. I'm just using the end of a nylon zip tie. You can just make out the copper bar at the bottom of the yellow port. Spring loaded fingers is what they are like.


I must admit I was a bit nervous putting the meter probes on the pins having heard rumours of any electrical current setting them off. But saw an airbag company video doing their testing this way so felt better about doing it. This is where I learnt how to check them as well. Both stages showed 2.1 Ohms resistance.


The passenger bag even had the plug with the same shorting bar. So did the same trick for both stages. 2.1 Ohms as did the curtain airbags.


So I shortened all the coils of wire for the sensors and curtain airbags. I bolted the sensors together. I also measured the resistance of the length of wire I cut out and it came to 0.3 Ohms. So the resistance valve I will use in the end of the shortened curtain airbag loom plugs will be 2.4 ohms. I did learn that they have a tolerance of 0.3 Ohms up or down to account for wire length and contact differences etc. I'd rather add the higher value to get it as close as possible to start with. Time will tell as I don't have them yet to try.


I have tucked the sensors under the other loom and on top of the padded isolation, as I don't want them bouncing around.


Just when you think you have done most of your looms, the headliner has a big one too! Looked a bit much for just the map and courtesy lights, turns out yet another module up there for the cabin temperature and compass receiver. Think there was an optional DVD player there too? Loom is all sorted and now installed in the Willys.


And look what happened. I nervously connected the battery and turned the ignition fob, wireless ignition in these, and the dash lit up. Accidently turned too far and it tried to start as well! No fuel in the tank though. Happy days.
 
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