ABS help

[mobilevet]

This might belong in the powertrain section but since I'm not sure I'll post it here.

I've got an ABS light on. It does not come on until after you hit the brake for the first time after start up and stays on until shut down. It used to come on some times but then if you shut down and re-started it would go off and stay off.

My sources say this is probably a sensor gone bad and that there are one each in the front hubs and then one in the transmission (or transfer case?).

Assuming this is correct, does anyone know how I can test to see which one of the sensors is bad?

thanks

[Robyn]

The 94 is OBD1 and can be checked with a simple code reader that allows you to select engine or ABS codes.

Select ABS codes, plug into the ADL connector (under the edge of the dash right ahead of the driver) turn on the key and count the number of flashes on the ABS light.

If its a wheel sensor, they wil usually not wait until you step on the brake to set the code.

My gut feeling is that its within the ABS unit out on the LH fender and is gonna cost $$$$$$$$$$$$$$$$$$$ to fix it.

Get the code and then we can figure out what it is for sure.

An ABS module is going to rip up $1000 to replace.

My DaHooooley has the same issue. Hating ABS the way I do, I just decided to ignore the issue.

Generally if the brakes are functioning well with a good solid pedal and full braking, this sort of issue is more of an anoyance than anything else.

If the brakes are not operating properly, then one needs to go after the problem.

One common problem with the ABS units is that the little pump motor will short out and this will set a code.

You can try unplugging all the electrical connectors and spraying them with cleaner and then plugging back in.

A poor connection can cause the problem too.

Keep us posted

Missy

[DmaxMaverick]

Being a 94, verify the system you have. It could be ABS, or RWAL (Rear Wheel Anti Lock). Suburbans may have only ABS as an option. Check it against your RPO codes (sticker in the glove compartment). If ABS or RWAL is not listed, then ABS was standard base model equipment.

A bad master cylinder will cause ABS issues and codes, among the other things Robyn mentioned.