85 325i ABS problems

[Driftit 1950]

Ok I have spent the last week trying to track down the problem with the ABS in the 325.

What happens is that the ABS engages even under normal light braking. Making it extremely dangerous. As it pretty much stops the car from braking at all. Once the ABS realizes there is something wrong it then puts the light on and turns the ABS off allowing normal use of the brakes.

So far I have replaced everything I can that is related to the ABS.

ABS Pump

Left and Right ABS Sensors (Also cleaned etc)

Checked ABS rings for damage. Replaced drivers side.

Brakes flushed

Both relays

There has been no change.

So what else could it be?

E30 Guru's only please as anything newer is totally different.

[c.robertson00 11]

Why dont you just pull it all out?

[Driftit 1950]

Because then I need to spend $500 on a cert plate. Not interested in pulling it out unless it is going to cost more than that.

[joshnz 2]

Stab in the dark .. but could it be the main ECU in the car?

[Driftit 1950]

I dont think the ABS system is linked to the main ECU at all. All the brains for the ABS is actually attached to the ABS pump.

But the car is being dropped at my mates Auto Electrical shop tomorrow to see if he can hunt down the problem.

[hotwire 352]

I dont think the ABS system is linked to the main ECU at all. All the brains for the ABS is actually attached to the ABS pump.

But the car is being dropped at my mates Auto Electrical shop tomorrow to see if he can hunt down the problem.

Don't think so. From memory ABS computer is behind glovebox. I have one if you need it

[*Glenn* 854]

Don't think so. From memory ABS computer is behind glovebox. I have one if you need it

The F/L E30 I wrecked a while ago had the ABS control unit in the boot on the L/H side by the aerial. I still have it here as well

Edited March 17, 2009 by *Glenn*