Bosch 5.3 ABS modules

[jay8086]

Hi all,

Thanks to the info here on the various symtoms my 306 has, abs light on, diagnostic light on, speedo randomly drops out for could be seconds or til the cars stopped, it looks like the module in my abs is shot. Mines a Y reg phase 3 so i'm sure its the bosch 5.3 setup. My question is how compatible / interchangable are these modules. I presume i need to look out for another front and rear disc brake, 1.8 or 2l, 16v, phase 3, but is that all I need to worry about to avoid reprogramming the module?
Secondly if I find a car to get the part off is there anyone on here near Oxford that knows how to swap the module without taking the pump out of my car. (Aparently the module can be changed with the pump in situ).

Thanks for any help and advice.

[jay8086]

Got and ABS pump / module from a Citroen Xsara 1.8 with discs all round. Turned out to be the right part number and a sucessful ABS repair .
I've written a guide and posted it in the guides section.

[HDIkyle]

Would it not have been easier to just unplug it? How does the ABS module affect the speedo dropping off ect?

[jay8086]

I thought it would be easier to unplug the module but after a day of trying to bend the pump around and not even getting to the bottom left screw, let alone being able to get the module off I gave up and decided to replace to whole unit. From what I have read the pump itself and most of the module are very well built, the fault is down to the wires inside the module connecting the pins to the board. I'm not entirely sure what the electrical link to the speedo is but during looking into fixes for the problem I read an advert along the lines of 'ABS light out, Engine light on, speedo dropping out then have your abs module repaired by us etc etc' and see there is some sort of wheel speed sensor circuit in the module, maybe they are linked?

It would be good if someone trying to do this could try to move the pump around to an angle they can get the module off. I couldn't but that's not to say it can't be done. The room around the module will also be affected by car age and spec, my engine bay seems pretty packed and there are other components too close.

[Niall]

Would it not have been easier to just unplug it? How does the ABS module affect the speedo dropping off ect?

It would be easier to unplug it but it would fail an mot for abs light on or not coming on at startup and you have no abs. For a 15 minute job, it's not exactly difficult!

[Toms306]

The speedo won't be to do with the ABS pump just so you know. SOME cars use an ABS wheel speed sensor, via the ABS ECU to determine the vehicles speed for the dash display. However 306s use a speedo sender unit located on the gearbox for this, so this is where you should be looking for that fault - either the sensor/sender itself or a bad earth seems to usually be the problem.

[jay8086]

Cheers Tom, great answer
That explains why the comany mention speedo issues and abs ecu fixes in their ad, and lets me know to keep an eye out for another issue, and possible fixes for it. Spot on mate