94 safari,no shift,no speedo,abs light


stan64572
02-08-2008, 11:28 PM
my 94 safari was running fine when parked.,stayed parked about a month.when ready to use replaced battery to crank but on driving discovered trans. wont shift out of low and speedometer dont work,also anti-lock light is illuminated. wiring to speed sensor on trans. seems fine.no blown fuses found,dont know what might have happened while it sat. please help.thanks

brcidd
02-09-2008, 09:52 PM
double check your "brake" fuse-it is toward lower part of fuse box. Mine did what yours does - and my ABS module was shorting out the speed signal circuit- so I cut the ABS feed and the fuse no longer blows (no ABS now) but at least it shifts and I have a digital speedometer.....It is a 15 amp and when it blows it does everything you described--primarily not shifting. I would guess your ABS module (too expensive for me to replace) has an internal short. If yours is like mine-it will blow the fuse again in a few days- so keep some spares-- I finally gave up and traced it to the ABS module and cut that hot wire so my van will shift, have a speedo etc.. just no ABS brakes==makes it like a '91 van when there was no ABS brakes- not worth fixing as far as I'm concerned..bb

stan64572
02-10-2008, 11:09 AM
can anyone tell me where the abs control module is located and what it looks like? It has been suggested that I cut the hot wire to disable. I would like to try this to see if it will solve some of the other problems, but I dont know what to look for.

brcidd
02-10-2008, 12:11 PM
Was your 15 amp brake fuse blown? You did not have to create a new thread- it is best to keep the discussion going in the same thread to get the entire story and circumstances so others can learn....

Anyway- ABS module is under master cylinder-outside under hood beside battery. To test for this as the source for a blown fuse-- merely unplug the module and see if fuse remains intact (no longer blows). the connection has several wires in it and is a fair sized plug.... always test first- before making disabling decisions

Blue Bowtie
02-10-2008, 02:01 PM
Depending upon your model year, the ABS power relay may be under the driver's seat, tucked inside the left subframe rail. You can disconnect the electrical connector there to isolate that as well.

stan64572
02-10-2008, 02:13 PM
I am new to this site so not sure if replying right.but anyway,the fuse was blown and will blow another as soon as key is turned on. I have checked wires to both front wheel speed sensors and wires to the speed sensor in trans, all seem ok. I disconected both wheel sensors and control module,still blows fuse immeaditly,checked wiring into fuse block from behind battery nothing found.

stan64572
02-10-2008, 03:04 PM
Im sorry blue bowtie,but its a 1994 gmc safari,with 4.3,auto trans. all three things happened at once brake fuse blew,anti-lock light came on speedo quit and trans wont shift. I would be happy just to get it to shift.

stan64572
02-10-2008, 07:26 PM
the 1994 GMC safari with no speedo or trans shift.... I just found that by unplugging the flat harness that is plugged in to the brake light switch,I now have speedo and will shift, but of course no brake lights. does anyone know how I might can get the brake lights back working without the other problem, in othe words which wire can I eliminate.

brcidd
02-10-2008, 09:21 PM
As I stated before- the ABS module is shorting internally- by unplugging the brake pedal switch you have disconnected the ABS hot wire feed (purple wire)so that the fuse no longer blows-- as well as your brake lights-- so if you want brake lights please plug that switch connector back in and unplug the ABS module plug out under your hood- under the master cylinder below and to the left of your battery--- also note that your ABS light will remain on all the time-- but you can always put some black electrical tape over it.....not the right way to fix things-- but who has got $1100 for a new ABS module???

If the brake lights were shorting- they would blow an entirely different fuse- (the stop lamp fuse)-- so to elimate just the offending element- just unplug the ABS module- or cut the purple wire in front of it - if you can't get it unplugged-- cutting the purple wire at the brake switch connector would do the same thing- but may interfere with your TCC release.....

.been there done that-- I didn't get 360,000 out of my '94 Astro without learning some tricks along the way.......

stan64572
02-11-2008, 07:23 PM
hi brcidd, thanks again for your excellent help with this safari so far,but I did unplug the module first at least I think I did, I found the module and there was a harness running to it that contained many wires,I couldnt get my hand down to the connector to unplug there, but the other end of the harness ran behind the battery where it connected with a weatherproof connector which fed to the back of the fuse box this is where I unplugged ,then still blew the fuse which is located at the bottom and to the right of the fuse box labeled brake i understand that I may cut the purple wire off the brake light switch connector to solve problem, but what is the TCC release you refered to?

brcidd
02-12-2008, 10:50 AM
To make things simple--if you can't unplug that ABS module connector at the connector- then snip the purple wire at the ABS connector, not at the brake pedal- make the cut at a point where it would be possible to splice it back at some time later. The purple wire at the brake pedal switch also feeds back to the PCM which would tell it when to release your transmission torque converter lock-up mechanism (basically keeps the tranny turning the same speed as the engine to improve mpg). If this was not active- then your engine would stall at stop signs-- so don't cut it att he brake pedal-- I did nnot have any trouble unplugging my ABS module connector- but I often use dental picks and the like to pull back on plastic tabs....

stan64572
02-12-2008, 07:07 PM
thanks brcidd, I just got home from work and read your last post,I will try that as soon as I get a chance,its dark and stormy here now.let you know how it turns out,Im going to try harder to get the wires unplugged at the abs module..

stan64572
02-17-2008, 07:20 PM
I now have the 94 safari going that wouldnt shift and no speedometer, blowing fuses. I cut the purple wire going into the brake light switch connector at the connector itself. The van will now shift,I have speedometer, the brake lights work, and dont blow the fuse,of course no antilock brakes

MN Safari
04-15-2010, 10:06 PM
Help! I am having this very same issue and tried disconnecting the ABS connector as well as clipping the purple wire with no success (fuse still blowing when braked pedal is depressed). I noticed that there are 3 connectors that plug into the ABS module- one on the right side (power?) when in the middle and one on the left side. I have unplugged both the one on the left and the middle (same time) and still blowing the brake fuse when the brake pedal is depressed. There is a flat 6 blade connector on the side of the brake pedal. Blades 1 & 2 and blades 3 & 4 (when linked) have continuity when the brake pedal isn't pressed while blades 5 & 6 have no continuity. When the brake is pressed the opposite occurs - blades 1 & 2 and 3 & 4 lose continuity while blades 5 & 6. Blade 5 has 2 orange colored wires and blade 6 has a large white color wire. Any ideas what these two wires lead to/from? Any other suggestions what may be blowing this fuse?

wireit
02-26-2011, 04:01 PM
Hi all, I have been having the same problem with my 1994 GMC Safari and when I located the ABS Controler under the break system there are 3 seperate harnes plugs attached to it. One of them has exposed cable and I can see the Purple but verry hard to get at and want to make sure the other 2 don't have a Purple cable also.
Also I haven't found a blown fuse and checked them all but canot pinpoint which fuse is for the ABS Controller.
Any help!

brcidd
02-26-2011, 08:22 PM
The fuse is labeled simply "brake" in the fuse box above your left foot under dash. Is it blown?

davemt64
06-11-2011, 11:35 AM
Hello all,I have a 1994 chevy astro van that lost the speedometer and has abs light on , checked fuses, all good ,even used ohm meter to make sure all fuses were good. Anyhow, replaced vss sensor and still not fixed, trying to locate a new wiring harness from vss to front of vehicle. Want to mention,before this happened , my abs control device was " growling " alot " everytime I stopped .Is the abs unit bad ? Im gonna stay on this subject until I get it fixed. Need to know if theres any way to test harness for a signal at the plug to vss ? ( 8-22-11) update : tested wiring to vss,rear wheels off ground ,getting signal both ways and when van rear wheels are off ground abs light stays off. Also tested front speed sensors with ohm meter,they must be good cause the value changes as I spin brake rotor. last resort is to try the purple wire at the brake modulator.This has been a interesting mystery.

buzzmonkey59
06-11-2014, 06:45 PM
i have the same problem except no abs light instead ac quit working as well as speedo and not shifting ive checked all the fuses they all are good the abs is disconnected and still not shifting and no speedometer everything else works gauges lights horn wipers any suggestions?i suspect ignition switch contacts because i wiggle the switch the speedo jump to 40 and the tranny shifted to 2 nd gear then the speedo went back to zero and the tranny stayed in second gear until i shut it off now its stuck in first again.

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