hmmm - quiz of the day.
Jumpering pins A - H on 12-pin ALDL, I get the following DTC flash codes (abs light)...
6 flashes - 8 flashes (x3) = 68
1 flash - 3 flashes (x3) = 13
3 flashes - 6 flashes (x3) = 36
3 flashes - 7 flashes (x3) = 37
Then repeats...

Can anyone out there tell me what my truck is trying to tell me?
Thanks.

BTW - The Truck in question is a '95 C1500 SLT
Correction -- Kelsey-Hayes 4WAL

Sounds like your screwed... J/K I think you actually have 4 seperate codes there. Go to troublecodes.net I think you will find what you need... good luck.

Hey 70Camaro - Thanks for the response and the resource (http://www.troublecodes.net/). Great site... Unfortunately, they only have the engine codes posted. I'm still having a hard time trying to find the chasis codes (OBD1/EOBD for ABS - ALDL pins A & H). I think you're right though... Totaly screwed.., and snow's coming. great.... :(

Did you you try a google search?

Did you you try a google search?
Yep... Been all over the World Wide Web. Amazing who all drives a GMC. This I did find:
6 flashes - 8 flashes... (68) = A locked motor or open circuit
1 flash - 3 flashes... (13) = System Normal for 2WD
3 flashes - 6 flashes... (36) = Missing left rear VSS signal
3 flashes - 7 flashes... (37) = Erratic left rear VSS signal

Conflicting? Yeah, pretty much. So.., does this mean I have a bad relay, motor or pump in the EHCU AND a failing or failed wheel sensor???
This is one of those situations that the more I come to find out, the more I'm confused?

BTW - In case anyone else is looking, here's some great info on ABS...
http://www.raybestos.com/OnLineTraining/

GMCTech... you still out there???