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ABS dead.

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Old Oct 6, 2009 | 09:14 AM
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ABS dead.

Ok here is the problem; I did a 0-60 run a while back when I launched the car the wheels spun a bit. Then I came to a stop. Didn’t slam on the brakes but gave firm pressure. It really didn’t feel right. The next day I was driving around town and had to stop hard, light changed red. The ABS light came on and it locked up.

Now when I hit the brakes hard it does it all the time, I have the aftermarket BBK Rotora. I’m thinking that the sensors are dirty? Or maybe the whole ABS system is bad? I changed and flushed the lines with fresh brake fluid and they still lock up. Does anyone have a photo of the sensors? How hard will it be to rebuild the ABS system?
I just hate my brakes locking up like they do.
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Old Oct 6, 2009 | 10:19 AM
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I'm not sure if the FD actually does this but usually a code is written to memory on the ABS computer and you should be able to read them to find the exact problem.
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Old Oct 6, 2009 | 10:43 AM
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ABS computer? Where can I find it?
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Old Oct 6, 2009 | 08:50 PM
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any other ideas?
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Old Oct 7, 2009 | 02:22 AM
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kinda worried about my ABS too. for some reason my ABS pump stayed on the other day even after the car was off.
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Old Oct 7, 2009 | 09:39 AM
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Should I replace the ABS pump?
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Old Oct 7, 2009 | 10:25 AM
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If you need one, mine was still working well when I removed it 3 years ago.
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Old Oct 7, 2009 | 11:20 AM
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Originally Posted by rotarshapedballs
kinda worried about my ABS too. for some reason my ABS pump stayed on the other day even after the car was off.

Over time the abs pump relay will stick closed when it gets hot. If you pull the fuse & wait for the relay to cool down it will operate normal again (until the next time the relay gets hot & sticks closed)

Short story..............


I got the ABS light & experianced massive front brake lock during an autocross event.

When I opened the hood I could hear the ABS Motor running. Even after I shut engine off & removed the key, the ABS Motor just continued to run.

I pulled the ABS fuses (40 & 15 amp) from the fuse/relay box near the left strut tower. This shut the ABS Motor off, but I still had the light & some serious front brake bias.

With the engine still off I put the fuses back in & the ABS Motor started running again, so I pulled the fuses to save my battery. After a while (1/2hr or so) I put the fuses back in & all was back to normal. It stayed that way for a couple of months.

Then during a lapping day I got massive front brake lock up (the right front tire taking the brunt) & ended up flat spotting my R compound tire to the cord. The F*cking ABS light was on again. Back in the pits, with the hood up, I could hear the ABS Motor running.

The ABS Hydro Electrical unit (r/h corner of the engine compartment, has two relays under the black plastic cover. One is for the Pump Motor & the other is for the Valve.

I removed & tested both relays on the bench with voltage. They operated normally. I heated the Pump Motor relay up to 250' F & applied voltage. The damn thing stuck closed. After it cooled down it snapped open.

That's why the system would return to normal if I waited prior to reinstalling the fuses.

During normal street driving you don't cycle the ABS much, if at all. On the track it must be cycling & generating a bunch of heat (due to high resistance & poor contact).

Summary?

I replaced both relays in the ABS Hydro Elect unit. They cost around $60 for the pair. They originals lasted 13 years, not to bad in my book.


ABS Motor Relay: NA23-43-7A2
ABS Valve Relay: NA23-43-7A3
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Old Oct 8, 2009 | 07:54 AM
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thanks for the info. So do you think its just the relays that are bad? Would they cause the brakes to lock up? I will change them out and see what happens. Hopefully that will do it.
Thanks again!
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Old Oct 27, 2009 | 10:14 AM
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Got it checked out. Whoooooohoo was dirty speed sensors. I called ray to see how much they were 212 each!!. Good thing I dont need them (for now).
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Old Nov 13, 2009 | 10:56 PM
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My seems to be having an issue now too. I'm going to check the relays and speed sensors. Is there a particular way to test the speed sensors and clean them? I'm hoping it's just the relay. A couple weeks back I heard the pump running even though the car was off. I just disconnected the battery cause I wasnt ready to deal with it at the time. Today I definitely could tell the ABS wasn't working.
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Old Nov 13, 2009 | 11:24 PM
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Turned out to be the fuse. But maybe that relay was stuck and burned out the fuse. It seems fine now.
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