ABS lamp

[nzvlnr]

1994 Chevy Blazer v8
I have an abs lamp when the vehicle starts moving and it stays on....( it will lamp up if I sit there as well).
How do I test the sensors to see if one is bad?

 

[MO Viet Vet]

Check to see if they are out of adjustment or dirty or has a bad wire or connection. If you have been in the mud or muddy/salty roads lately it could be as simple as that.

 

[nzvlnr]

Actually the truck has had this ever since I bought it 3 years ago..I have done a front brake job on it abt 500 miles ago.....I cleaned the sensors.....how do I check for a bad one? I am selling it and would like that lamp to be corrected.

 

[lesterl]

Ohm out the sensors. there are 2 on the front and the VSS is for the rear wheels, the ABS module is probably bad tho.....

 

[nzvlnr]

Can I pull the code to find out what is bad...or does a shop with the proper ODB I tester need to pull it....scan tech II is the scanner?

 

[adam74]

put a paper clip between two ports on the obd1 plug and check them as if you were checking the cel codes. let me try to see which ports they are again cant remember off hand

 

[adam74]

OBDI, which means you can get the codes using a paper clip. just find the little data link connector thing just under the dash below the steering column. you need to make the connection between the A and H terminals: A (ground) is the the top row on the very right; H is on the bottom row, second square from the left. watch the <font color=red>anti-lock</font color=red> light on the dash...count the flashes in groups...for instance, a group of 4 flashes and a group of 3 flashes means a code of 43.

 

[lesterl]

Sounds right Adam, didnt want to try to explain something I couldnt remember all the details on tho.....

 

[nzvlnr]

Ok...A and H....I will look for the pin out on the ODB I ...I was under the impression that codes for the ABS needed to be read from a SCAN II device?
Anyone have the pinout on the ODB I? I am not at home with all my documents....looking now

OBDI, which means you can get the codes using a paper clip. just find the little data link connector thing just under the dash below the steering column. you need to make the connection between the A and H terminals: A (ground) is the the top row on the very right; H is on the bottom row, second square from the left. watch the <font color=red>anti-lock</font color=red> light on the dash...count the flashes in groups...for instance, a group of 4 flashes and a group of 3 flashes means a code of 43.

 

[adam74]

yeah you could pay a shop to read em for you or you can do it yourself for free lol

 

[adam74]

http://www.s10planet.com/forum/showthread.php?t=26292

should be helpful here

 

[nzvlnr]

Awesome......much appreciated....Happy New years to ya!

 

[lesterl]

If you look close at the terminals you should see the letters....
http://www.obd-codes.com/faq/read-gm-2-digit-obd-codes-free.php

Top Right most is A
Bottom Left (go right 1 pin) is H

 

[nzvlnr]

So I paper clipped pins A and H and I get a count of 1 and 4....Problem is there is no code for that. There is a high temp code, but I am pulling codes for the ABS not the engine diagnostic?

 

[MO Viet Vet]

I binged this....

ABS code 14

A code 14 is the Enable Relay circuit open. It could be a bad ground, a bad Enable Relay or the Abs hydraulic unit is defective.

 

[nzvlnr]

I binged this....



ABS code 14

A code 14 is the Enable Relay circuit open. It could be a bad ground, a bad Enable Relay or the Abs hydraulic unit is defective.

What is an enable relay and how do I track something like that down? I guess a schematic would be the way to track it down?

 

[MO Viet Vet]

If I don't know it or have it I google/bing it and see if can get a schematic.

 

[lesterl]

http://www.truckmodcentral.com/forums/f23/pulling-chevy-truck-obdi-brake-codes-information-6609/

Looks like an internal fault of the ABS module.....

 

[Ice98]

I have heard of this problem being quite common, what happens is that the actual sensors in the wheels will have any number of things happen to them, either wearing out, becoming corroded, spacers wearing out, etc, its pretty easy to check and replace the sensors but you will need a decent multimeter

https://www.youtube.com/watch?v=Ld5-eoYGAiA