Abs and vss problems?
 

I have a 94 gmc jimmy 4.3 w. I was on the highway and went over a pretty hefty bump. I then noticed the speedo stopped working. I went to re-engage the cruise control and noticed that it too stopped working. Then the abs light came on. By the time I was close to home the check engine light also came on. I got off the exit for the highway and went to accelerate and noticed that the transmission had gone into limp mode. It took a while getting back to my house not being able to shift but I kept the RPMs as low as possible.
I checked the codes and they were a 16 and 72, which I found have to do with speed error and vss signal loss. I replaced the vss hoping it would be an easy fix and cleared the codes. No dice.
I checked the abs codes today and I'm beginning to wonder about a fault with the ecm perhaps. I got codes 41,42,51,52,(12,in the middle of all of these not at the beginning)37,45,36,46,65 and 67. Phew! That's a lot. It seems crazy. Does anyone have a clue? I have no idea about abs. I took the front tires off to check the wheel speed sensors and everything looked fine, no obvious wiring issues. I was thinking perhaps speed sensor buffer? or bad ecm but I don't want to take a shot in the dark.
Any help would be super appreciated.

-Melissa

Anyone? Please?

sounds like you got a bad abs module. since all them problems started at once. read this for code information. some of the codes you mentioned arent even codes for this blazer anyhow....ABS TROUBLE CODES - OBD1 & OBD1.5

and i think you had the same problem i ran into. i had 17 codes come out of the abs light. even code 12 witch means the computer is working right but it aint. anyhow i took my abs module off the main computer. its under the passenger side dash holding up by one 10mm bolt. pull it down and there should be two little boxes attached to a big box. the smaller metal box is the abs module. bend the tabs out so you can take it apart. and look at the capicitor real close. its a tower like piece that stands up off the board. is the top bulged or is brown slime oozing out of the top of bottom. if it is then just replace it. and it will work again. i took mine apart and found that that capacitor was bad. took one off a tv board and walla worked ever since. oh and wiggle the capacitor a bit and see of its really loose. mine was corroded so bad it just fell off. check out my last post on my thread .... https://blazerforum.com/forum/1st-ge...ms-help-58349/

Thanks for your reply. Problem solved. We pulled the ECM out from under the dash. The abs module looked brand new. The vss buffer had a little crack in the plastic box. Had a mechanic friend test it. There was signal in but no signal out. Replaced the buffer and repaired some wiring between the vss and the buffer and she's good to go. Thank you. :)

I checked my ECM codes by jumping with a paper clip. I got code 37 too, but not checking the abs. What gives? Any ideas?

Did u ever get the problem figured out?

how many miles do you have on your ride...Did your abs/brake light come on the dash?My abs/ brake light has been staying on since I bought mine.I ran a test on the abs system as a whole.Come to find out, the abs module wasn`t functioning correctly.I bought a new abs module..Installed it.No more abs or brake light on dash.FYI you see a bump in tha road, slow down or go around it if you can.I woud take it to your mechanic so he or she can hook up the scan tool..Then go from there.Good Luck!

This thread is 4 years old, and Eff10 hasn't been on this site since Nov 2014. You're not going to get any answers from her, not to mention her problem was fixed by replacing the VSS buffer as she mentioned. :icon_wink: