ABS diagnosis

[SGratz]

One of my e30's (the '87) has the ABS light on and I would like some help in diagnosis. Other than visual inspection of the ABS sensors (front and rear) is there any further testing I can do to find the fault?

[whosyadadie01]

you can check the abs relay. other then that theres not much else you can do without a abs code reader

[SGratz]

Thank you for the reply. I don't have, nor do I plan to buy a code reader so this might just be a job left to the $100 per hour guys.

[whosyadadie01]

a normal code reader wont read abs codes, it would have to be a abs specific reader and you normally wouldnt buy one unless you own a shop

[drivinfaster]

check the fuse. check for cracks in the insulation on the sensor wires. check for a bad wheel bearing (REALLY LOOSE), check the resistance of the sensor with an ohm meter (multimeter). check on the spec for ohms and use that scale (9 ohms and 9k ohms are two different scales and will not read properly on the wrong scale)
a misconception of abs is that somehow your brakes will not work properly, but no, they will work fine. they'll just lock up on hard braking. abs prevents this by a series of motors and solenoids to control the hydraulic pressure.
also, any shiny spots on the abs wheels (toothed gear-like rings) are a sign on rubbing. but look for the simple things first. good luck.
drivinfaster