i have a 96 disco 1 and the horn and cruise have not worked since i bought it.
both the srs and check engine lights are on. i have checked the check engine light and it is just a o2 sensor.i am guessing the rotery cassette is bad it there any easy to check this? also i need to replace the rear drive shaft and yoke for the rear diff as the previous PO let the rotoflex fail and still drove it till the flanges are badly damaged. I see conversion kits from lucky 8 great basin and Atlantic British is there any real differences? just buy the cheapest? i have thought of just welding the damaged areas of the flanges but feel they would be much weaker than stock. i am planing on a 2" lift and moderate offroading well i think its moderate lol but i already bent one of the rear links
any advice would be helpful.
Cassidy

 

Other than having the SRS codes read by a specialized scanner, your deductions are about as good as you can get. Your logic is sound, I had a similar condition with my DII (except the horn worked but the cruise didn't unless the radio was turned off). Even with a code scan it's still somewhat of a guess. I have access to a scanner and it showed "Open circuit fault in driver air bag circuit". So I "guessed" the rotary coupler since that's the only place where the 2 systems interfaced. Instead of spending the big bucks for a new coupler, I got one from a used parts dealer for $55.00, took care of the problem. (and no, I didn't have to have the codes erased). If when you first start the vehicle and the SRS light comes on, goes off after a couple of seconds and then comes back on, it's a good sign that the ECU is performing it's self check and found a problem. If the light comes on and stays on without momentarily going out, the problem would be elsewhere. This is all on a DII, I think the DI system works the same but not entirely sure, been a while since I worked on one.

 

I have a 1996 DI, my cruise hasn't worked in years, then the SRS light came on and the horn stopped working. I replaced the rotorary coupler and the horn works, SRS light went out, but the cruise still doesn't work. I bought the coupler on eBay for about $20 and it worked great, easy to install too.

 

On MOST vehicles if controls on steering wheel don't work it's the clock spring

 

thanks for the helpful and not so helpful responses