ABS ECU

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mcgregor
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ABS ECU

Post by mcgregor »

Hi
Can anyone tell me where the ABS ECU is located in a 2001 Xantia HDI 110 please. I have an ABS alarm light up and I suspect it is one wheel sensor and need to check out the resistance but I have no idea where the ECU is located. Any help gratefully accepted.
Cheers
Dave
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Post by addo »

Dave, are you able to get any more specific information from the diagnostic socket under the dash? I've never had an ABS fault, so I don't know how specific the logging is.

From memory, my ABS controller has a multipin plug on it, so the ECU may be self-contained.

Regards, Adam.
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Post by mcgregor »

Adam
That is exactly what I am looking for (the ABS ECU multiplug) Where is it? Is it under the bonnet or under the dash?
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Post by KP »

It on the passenger side of the engine bay usually just in front of the LHM resevior.

Should have a good few pipes into it and then the multiplug on side or top depending on varient.
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Post by mcgregor »

Brilliant. Thanks very much.
Dave
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Post by mcgregor »

I found a photo of the ABS unit plug in a previous thread so I tested the plug last night and got results of 3 out of the 4 showing 1070 ohms while the LHR (is that N/S?) showed 1028 ohms. Is a 42 ohm loss enough to be giving the problems with the ABS unit? Sometimes it resets and the light goes out when I first move off but then it returns after a minute or two.
As before any info gratefully recieved before I go out and spend £60+ on a new rear sensor.
Cheers
Dave
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Post by CitroJim »

mcgregor wrote:Is a 42 ohm loss enough to be giving the problems with the ABS unit?
In my experience Dave, yes :cry: The ABS ECU is very sensitive to even small changes in sensor resistance. 42 ohms is enough.

If you could get your car on a Lexia, you'll find the iffy sensor is reported as being out of specification and every now and again it will light the ABS warning lamp.

Shame it's a rear sensor as they're not as easy as front ones but on the bright side, at least they're a little cheaper :)

It'll be worth just checking the sensor connector for dirt and good contact before ordering a new one though.

Sorry to be the bearer of bad news Dave :(
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Post by mcgregor »

Thanks Jim you really just said what I was thinking. Still not sure about LHR though. Any thoughts?
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Post by CitroJim »

LHR is indeed the N/S Dave. L and R is from the viewpoint of sitting in the drivers seat.
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Post by mcgregor »

I thought it was but needed confirmation. Thanks very much Jim.
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Dave
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Post by KP »

I have a full rear swing arm if you wanted to make the job a bit easier comes with hub as well?

Depends where you are though as they are very heavy....
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Post by mcgregor »

Thanks for that but I live in far NE Scotland, but I reckon a sensor change will not tax my abilities too much.
Cheers
Dave
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