ABS not working without cluster


Apologies up front; this is not specifically a spece30 question, but I have a feeling you guys can help.
I just bought an '88 325 race car and the previous owner removed the stock cluster. The ABS isn’t working. My guess is that there is a speed or tech signal that comes out of that cluster and feeds to the ABS module. I am familiar with e30 wiring and wiring diagrams, but I am not finding anything obvious and I am not sure if there is a work around. Any thoughts?


So if the aftermarket cluster has no ABS light in it you have no basis to troubleshoot this, that light is kind of everything. I just went thru this with my car. When the cage was done and the dash was out the installer never put back the two small push on connectors that run the ABS light. Once I got that working it was easier to find the bad speed sensor. For you? Does the car still have the ABS pump? Are all the speed sensors installed? Does the car still have the ABS computer and relay (drivers side underneath)? You can also see these with the cluster removed. Find out what parts are missing. Lastly you can test speed sensors with an ohmmeter, but my bad sensor had the correct resistance and was still bad.

Once you have all the parts IDed, you could source or borrow an OEM cluster (assuming you still have a dash that will hold one).


Sorry. I should have mentioned that I did check the other items, everything is installed, intact etc. and the previous owner did state that when he removed the cluster, that’s when it stopped working.


Here’s what I know about the ABS system on a E30:
You might not need the original cluster, but you definitely will need to either put the light somewhere in the dash, or rewire the 2 little wires that go to the light for the ABS (in-cluster light); that’s ‘continues’ the loop, enabling the whole system to work. The light comes on at ignition ON, then after the start it will/should disappear–as you drive, if there’s an issue (with the ABS system–wheel sensor or relay or fuse) the light will reappear. Needless to say, if the light bulb burns out (never illuminating on key on) then the ABS system will not work either. I hope this helps. Ray


Awesome! Thanks man! I figured after all the usual stuff tested ok that it had to be something stupid like this :wink:
I’ll report back with my results.