Brake warning light on for no apparent reason

[sasjzl]

Hi all,

I have a 1995 e320 wagon and the amber brake warning light has been on intermittently with no correlation to the use of the brakes. Sometimes it will stay on and flash what looks like the same rhythm as the wheels are turning. Any ideas on what would cause this? Of course I have checked all the pads, and the wiring to the front pads and everything is fine. The brakes work per usual. I thought that light was only supposed to go on when my front pads were getting thin. I see the sensor for that up front but do not see it in the back. Is it supposed to be in the back also?

I am wondering if it might have something to do with my ABS system except that has its own warning light that I have never seen go on.

Thanks very much,
Jim Lee

1995 e320 wagon 225k miles