ABS, and electrical issues

jludorf

Registered User
I have a 91 sc that is acting up.

while driving to work the power brakes stopped working. so the car was limped home.

Tonight we checked the brakes out and the booster/ accumulator does not seem to be leaking. I changed the abs relay on the firewall and it still does not work.

During testing we noticed that a bunch of other electrical items were not working as follows:

-daytime running lights
-no heater fan but you can hear the vacuum actuators activate
-no VMM
-no rear defrost
-no signal lights
-arc system is not activating, the car had the firm light flashing before

I pulled codes for Koer, Koeo and memory and have the following


KOER
6- I can find anything in the code reader book
538-Insufficient RPM change during KOER dynamic response test

KOEO
111-system pass
212-loss of ignition diagnostic monitor signal/spout cuicuit grounded
214-cylinder identification curcuit failure

We check all the fuses under the dash and all the ones in the fuse box under the hood. The car is an automatic and the windows, mirrors, sunroof, cruise, trunk release, locks, headlight lights and hazards all work. I do not think the accumulator is the problem I think there must be an electical module failure but need help to know where to start. I have tons of parts so if swaping out items will help just give me some ideas as I am stumped and my friend would like to drive his car again.
John
 
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i dont know much about electrical or for the matter cars yet...but that sounds like alot going wrong at one time....did it all start at the same time or has it dropped off gradually. do you have an eec that you can switch out? and i would think the rpm and dynamic code is because you didnt give it the gas when it wanted you to on the self test. well i take that back..eec should be controlling fuel air spark and such so if that was the problem the car would be running really rough i would imagine...must be another module or bad ground somewhere
 
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The strange thing is the car runs perfect. we changed the dis due to the 212 code but it did not seem to make a difference but the car still runs great. All the items that fail happened at the same time. When he pressed the brake pedal down to slow down for the corner the meassage center went out and no brakes. I'll have to see if I have an eec with the correct code on it to swap out.


John
 
Wow.. that doesn't sound good. I'd get a wiring diagram (www.alldatadiy.com has electronic versions) and start tracing down each circuit to find where power is getting held up from. Could very well be a bad ground. Maybe start by checking ground straps at the block. (down by the forward bolt on the motor mounts.
 
i had the same problem. my abs didnt work right either. i think the part is called an electronic ignition control. the part is located in the steering column below the ignition switch. you can get the part at advanced autoparts for about $12. i changed it and it fixed all my problems. beware though, it is held on by 2 security torx screws. good luck and i hope it fixes your issue also
 
I'll try testing the ignition module and rob one off a parts car and if that does not work I'll try the eec.
Thanks for the help.
John
 
Have you checked all the power leads yet??

Also Almost all the grounds are interlinked with each other.. So i would check the quality of the grounds too..
 
I inspected the ignition module thaqt is held on by the two safety torx screws and it fell apart in my hand so we put a new one in and everything is back to normal. Thanks for everybody's help.
John
 
not sorta... That is an ignition switch. It's an electrical switch driven by the lock cylinder rod. The lock cylinder is what you put your key in and turn. The switch is actually down the column further and is that item you linked to.
 
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