Thanks all. 2000 Taurus Wagon, 195 000km. The brake warning light on the dash stays on most of the time. The brake fluid resevoir is full, and the low level sensor plugged in. The parking brake works, and the switch on the pedal appears in working order. When the light has gone off, I've applied the parking brake and noticed that the light did not come on.
This must be a pretty simple circuit. Does anybody have a wiring diagram? Does applying the parking brake just ground out the switch? I'm hoping this is another common Taurus problem. I need to get this fixed for a safety inspection.
Inspect the float inside mastercylinder
E. Brake switch located at rear back of the handle
March, 1, 2012 AT 11:43 PM
If the float is inside the master cylinder, how can I see it? The switch for the e-brake has been inspected and appears to be working fine.
March, 4, 2012 AT 8:01 PM
Unplug the connector at the master cylinder to see if the light comes on. If it does not, plug it back in and retest.
One way of testing the switch is to use an ohmmeter to test for continuity. When fluid level is good, there should be no continuity between the 2 terminals of the switch.
March, 4, 2012 AT 8:18 PM
It appears the ABS module is the cause, as there seems to be no communication with it. The ABS/traction control lights don't self-test on startup, and it seems the t/c is not working. The switch for the parking brake was faulty, and has been repaired. I replaced the switch at the master cylinder with no luck, but found the light stays off when it's unplugged. Good enough!
March, 4, 2012 AT 8:31 PM
Yes, a fault with the ABS system can cause the light to stay on. You would need to get a scan done to check for trouble codes and proceed from there.