Abs fault.

[Sanchez]

Hi

I’ve a abs light on 1989 Touring, light goes out then on indicating a sensor fault.

I’ve read that a e36 should read approx 1.05 ohms front 0.95 rear but I get no readings on all but I did the test in a rush so will do again when time allows.

Question is finding replacement sensor at a good price and is there any other ways to test a faulty sensor.

I’ve new brembo discs and green stuff pads up front and drivers wheel locks up when hard braking, does this mean that sensor is faulty?

Please advise.

[paultv]

If the light comes on with ignition then turns off - then comes on when you drive off it will be one or more sensors at fault/wiring to the sensor(s)

Here's how to test:

If the light goes out after engine start and only comes on when the car is
moving, there's a problem with one (or more) of the sensors. The simple test
to find out which sensor(s) is the cause is to disconnect all but one of the
sensors and drive the car. If the light comes on, that sensor is sending a
speed signal to the ABS and is good. Repeat with each other sensor to find the
one(s) that don't cause the light to come on. Since the ABS module has no
speed input besides the wheel sensors, if only a bad sensor is connected the
module can't tell the car is moving and thus doesn't fault on missing speed
signals from the other wheels. Once a bad speed sensor is found, if a new
sensor still doesn't work, there could be a wiring fault in that circuit or a
bad input channel in the ABS unit


Paul

[Brianmoooore]

You can also disconnect the plug from the ABS ECU and connect an AC voltmeter to the pairs of pins from the four sensors as the car is being driven along. All four readings should e similar for a given speed.
ABS circuit here: http://www.autolib.diakom.ru/CAR/BMW/19 ... /fig06.pdf

[Sanchez]

Thanks.

[Sanchez]

Did Paul’s test and found nsf not to activate the abs light.

I’ve found a spare sensor in the spares box and will fit it Sunday.


Many thanks.

[Brianmoooore]

Be aware that front sensors are handed. Wrong one will sit at 90 degrees to what it should, and give close to zero output.

[Sanchez]

Thanks Brian.

[Sanchez]

Typically is the wrong side.

Can I fit it 90 degrees different and make a bracket?