Abs going crazy

[SgtMarshal]

I put in an engineered performance limited slip differential and have been running it for a few months. Lately the abs has been activating even though I turn off the traction control. Any ideas?

[Scottydoggs]

tc and abs, are not the same thing. tc is to minimize wheel slip. abs is the brakes not locking.


if you cant find a hub with play, or a hub wire off, or damaged wires to the hubs its best to have it scanned at a shop. or your just tossing money blindly at it.

[SgtMarshal]

I see what you are saying, they work together but they are still seperate. I am going to check the speed sensors and wiring for any issues next week

[Scottydoggs]

yup, but both work off the sensor in the hub. if the hub is bad, or a sensor is bad, you get the abs / tc lights. and a brake light sometimes too.

[SgtMarshal]

no lights no codes, I can just hear the abs pump modulating

[Scottydoggs]

that could be the ebcm going bad. its what all the wires to the abs pump plug into. its rebuildable.


most when this thing goes bad say the abs pump kicks in when driving slow and turning, like into a parking spot.

[Scottydoggs]

http://www.grandprixforums.net/threa...S-Off-Solution

[SgtMarshal]

I've read through that before, I just wasn't sure if the LSD wasn't causing it

[Scottydoggs]

its shouldn't be. all the info comes from them speed sensors in the hubs.

[SgtMarshal]

ive had the abs wire harness on the drivers side repaired, replaced the ebcm, replaced the wheel hub on the passenger side, so based on things that havent broken yet it could be the driver side hub, or the wire harness on the passenger side. or one of the parts I replaced could have failed.

[Booba5185]

Check all 4 hubs at the EBTCM connector, no need to jack up the car or anything really. Just check the impedance of the 8 wires (2 per wheel).

2&3 are Rear Right
4&5 are Front Right
22&23 are Rear Left
20&21 are Front Left.

[SgtMarshal]

How much resistance should there be?

[Booba5185]

IIRC mine was around 1000ohm. Mainly you want all 4 to be close to the same (within 5-10 ohms).

[SgtMarshal]

are you putting one lead on one pin and the other lead on the adjoining pin? like are you putting one lead on 2 and the other on 3? I have a bad habit of over complicating simple things unless they are painfully obvious.

[Booba5185]

Correct. On my meter I ended up just putting it on the continuity setting. It didn't beep (if your meter does) it just showed the reading, something around 1000.

[SgtMarshal]

three of the readings were ~ 900 and one was at 1035.

[Booba5185]

There's your sign, the EBTCM is constantly trying to match speed (IE apply brakes) to the other hub (front go together and rears go together) Whats the problem child?