ABS stopped working some time ago. I didn't bother since the car was stable even on slippery road. Recently the BRAKE light was on. I checked the fluid level and the braking (depressing the pedal, engine on/off, multiple depressing with engine switched off, etc) - the system looks leakless and airtight. However, the BRAKE light appears someties without any sign of malfunctioning.

The circuit diagram shows three possible reasons for the BRAKE light to be on - low brake fluid sensor, park brake switch and ABS control unit itself.

As far as I can see, the sensor and the switch are OK.

The question is - where to read the ABS codes and test the ABS control unit?

Autozone and pepboys don't do that. My enhanced OBD-II scanner can't read the ABS codes.

Thanks.

P.S. Where do people buy the ABS control units and what is the difference between the cheapest one ($147) and the most expensive one ($290)?

$143.

Sorry, couldn't help myself. Good luck!

I think in that year range GM used a brake malfunction lamp with a three-stage intensity indicator...I thought the first step was to step on the e-brake, and if no change in the light's intensity, an e-brake fault is indicated...if it gets brighter when you apply it, it's hydraulic fault/level sensor, and so on...anyone back me up on this, or did I hallucinate it? :uhoh:

I thought the idea was to point you in the correct direction to find the system causing the problem...you try pulling the manual release lever down at the e-brake pedal pivot and lift the pedal, see it it goes out?

I didn't notice anything special with the brightness of the light. It is either on or off.

As for the park brake switch - I disconnected its wire to be on a safe side that nothing is contacting the ground. The light didn't switch off. I didn't do that to the fluid level sensor thinking that it should be OK when the brake fluid tank is full (actually, it is not guaranteed and I have to check it as a last resort).

Regardless of this - how does the ABS control unit look like? Neither the online shop nor the Haynes manual does provide a picture and/or location. I guess, it's a metal box that is located somewhere between the steering column and the park brake, isn't it?

OK, it's definitely an ABS control unit - when I pull its fuse out, the BRAKE light goes OFF that means that the ABS unit wants to tell me something. OK, it's a kind of relief :) since I don't have anything against driving without ABS but I wouldnt' like to have an unknown malfunction in the brake system.