#073

[Herman]

I managed to get 1/2 hour looking at the 260 this morning. I made up an ABS extension lead using a spare connector and a length of twin cable. First I connected the 260 loom onto a known good sensor on my ZTT and it made no difference, suggesting that its the loom side in that's the issue. Just to double check I swapped the extension over and connected my ZTT loom to the OSF sensor on the 260 and the ZTT ABS light went out as expected suggesting it passed the start up test and confirmed the sensor is not the immediate issue.

So what should I check next? Replacement ABS ECU? Are they the same as other models? I know someone has played with the wiring before as I can see where the loom has been spliced into where it connects into the ABS hydraulic unit. Does anyone have a schematic of the ABS system?

Cheers,
Rich

Here you go:-
ewd_260_04MY_EN.pdferl260.pdf

[WNJ516]

I think I would try and use your extension loom to verify from the ABS plug unit to the sensor is good before condemning the abs control unit, disconnect the ztt good sensor and from ztt main plug use your loom to attach to the faulty circuit on the zt plug, hope all this makes sense, at least you know which way to go or what is faulty.

[Richb]

I think I would try and use your extension loom to verify from the ABS plug unit to the sensor is good before condemning the abs control unit, disconnect the ztt good sensor and from ztt main plug use your loom to attach to the faulty circuit on the zt plug, hope all this makes sense, at least you know which way to go or what is faulty.

I think I tried that Nigel, I plugged the 260 OSF sensor into my ZTT main loom and the abs light went out after a second or two. I couldn't onviously drive it anywhere but the fact the light went out means it passed the start up test with the 260 sensor plugged in.

Cheers,
Rich.

[Richb]

Here you go:-

Thanks Herman. Does that mean the abs ecu is part of the modulator rather than a separate ecu? Suppose that would mean removing the whole modulator and associated brake pipes to get it repaired or replaced?

Cheers,
Rich.

[Herman]

Thanks Herman. Does that mean the abs ecu is part of the modulator rather than a separate ecu? Suppose that would mean removing the whole modulator and associated brake pipes to get it repaired or replaced?

Cheers,
Rich.

ECU can be separated from the unit. Not sure if the can be done in situ though. Here's a pic of a BMW unit.

DSC-ABS-Module_10-2008_7.jpg

[stevenw]

It can be done in situ,it's not that difficult as long as nothing's rusty or seized.

I think it took me about 15 to 20 mins.

I used a flexible screwdriver with a Torx bit and had to loosen the power steering fluid reservoir and fusebox to gain access to the 6 bolts if I remember correctly.

I tested to see if it was likely to be the ECU by plugging in a loose known good ECU when the light was on .

It took about a minute to do and the light went off,but came back on when the original ECU was plugged back in.

[Richb]

Thanks for the info guys. I'll try and get mine out and have a look.

Cheers,
Rich

[Richb]

So I did a bit more digging. First I checked the loom as it had been butchered in the past. It seems 6 wires had been cut into, the two wires that go to OSF sensor, the two wires that go to the NSF sensor and the two wires that go to the instrument cluster. The good news is the wires to the sensors buzzed out correctly and I assume the wires to the instrument cluster were some half-ar##d attempt to put the light out!

So since the sensor wiring checked out, I looked at the modulator. I could see signs of tampering on that too, with "void" stickers on it where the security seal had been removed. On taking it out, I also found that it was only held in with 5 of the 6 torx screws!

So here are some pics of the removed module. Note that the part number is 0 265 900 047 which differs from the quoted part number in other threads but I've seen someone mention this one was fitted to their 260 too.

So, the question is should I have a dig inside? Or would that make potential repairers less likely to touch it?

Rich

[Richb]

Oh well, too late now I guess. There certainly looks like signs of attempted repairs in the past. Hope this one is salvageable. It also looks like a thin black jumper wire was stuck in the hot glue when they sealed the top back on and it pulled off with the top, so hopefully a repairer will know where that goes!