The brake light on the dash of my '91 S-10 4x4 Blazer with 4.3L won’t turn off. What could be causing this?
If you would read your owner’s manual, you would see that it is most likely indicating that your brake fluid level is low. If it is, then either yours pads are worn down or you have a leak.
Low brake fluid level or a stuck parking brake switch.
Check the fluid first.
Step #1–Check brake fluid and add to the “full line” if necessary
Step #2–Have a competent mechanic check the brake pads for wear. (As the pads wear, the brake calipers extend, thus drawing fluid from the master cylinder) If the brake pads are in good condition, have him check for a brake fluid leak, as brake fluid does not evaporate, and a low level indicates either worn brake pads or a fluid leak.
Step # 3–Read the Owner’s Manual!*
*If you don’t have a manual, you need to get one.
E-bay is a good source for cheap copies of manuals.
In case you think that you don’t need a manual, your question indicates otherwise!