ABS & 4MATIC Light come on on 1992 Mercedes-Benz 300TE 4MATIC

My ABS kicks in hard when I brake. I keep my foot on the brake and it fights me! It is pushing up and takes longer to brake. Sometimes I wonder if she will stop. The 4MATIC light comes on too. Does this mean there is a problem with the 4MATIC or that it is engaged? Same with the ABS light.

by in Plattsburgh, NY on December 13, 2010
1 answer 3 comments
ANSWER by on December 30, 2010
the 4matic system shares the same wheel sensors with the abs system. If a sensor is shot both the ABS and 4matic systems will be rendered inop. if your brakes are 'fighting" against your applying them, the faulty abs/4matic sensor is telling the abs computer that you are slipping in a wheel and is trying to control braking pressure. just push harder on the pedal, the abs will disengage. The bad news is when the diagnosis is that the problem is on the front driveshaft sensor teeth, not the sensor itself which is in the hub. the whole front shaft needs to be taken out and reconditioned or replaced ($$$) because the teeth are so corroded the sensor gets bad or no info, hence the wonky abs brakes.
COMMENT by on December 30, 2010
Thank-you for your reply. I appreciate it.
COMMENT by on February 09, 2011
this could also be a charging issue. Test the AC [not DC] output at your battery while running. AC s/b less than 5 volts. If more,rebuild alternator
COMMENT by on February 09, 2011
Thank-you!