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[maracus]

I was giving my mv6 an oil fluid change as I wasn't sure when it was last done and the brakes felt a bit crap and spongy. I refilled and bled, tried the car and they still felt crap, the pedal seems to go pretty much down although (possibly) not definitively to the floor, pump up ok if you pump the pedal but so very slowly goes down, (there's no external leaks) so back into the garage and got my brother over to help thinking I maybe hadn't bled all the air out properly and we checked it and was happy they were free of air but the brakes stillfelt crap.

It was then that we noticed a swoosy-clicky sound seemingly coming from the abs unit as if a valve or something is buggered, you can hear it kind of clucking as you pump the pedal. It makes this noise if the engines on or off. Could it be that this abs unit is indeed shagged, or is it possible that there's air still trapped, causing this noise?

I also have a presence of abs light, tc light and no speedo, I'm unsure if this is related or not but may be relevant..

Basically the car will be going, I was trying to get the brakes good for an mot but tbh if I need to start messing about with getting the abs unit swapped over id rather shift it spares or repair and get it gone, it looks a pig of a job!

[TheBoy]

Symptoms sound like master cylinder, or air.  Never known the hydraulic unit of the ABS to fail.

Ideally, see why the ABS lights are on - if it is the usual ABS failure, that doesn't normally affect hydraulic side of things.

If the car is being sold off, you may not get your money back fixing these issues 

[maracus]

Symptoms sound like master cylinder, or air.  Never known the hydraulic unit of the ABS to fail.

Ideally, see why the ABS lights are on - if it is the usual ABS failure, that doesn't normally affect hydraulic side of things.

If the car is being sold off, you may not get your money back fixing these issues 

Am I right in thinking I can check it on techII for abs codes?

It could be air still in the pipes that are above the abs unit.. I had bled until no bubbles were present at the calipers, could it be that I need to flush a lot of fluid through to get all the air out and didn't do it long enough?

I was using a crude stethoscope device I made with a steel pointed tent peg and a sink plunger cup, the sound was not heard down this tube when touched on the abs unit but on the pipes above it, the sound is definitely in this area where it's migrating from, though I'll pay a closer attention to the master itself..

As for cost, assuming the units are the same I can swap off my pfl cdx, but it's not so much that what I'm bothered about it's the time doing it 

[maracus]

Should I have bled the brakes in a particular order? I just randomly went round them...

[Andy B]

Should I have bled the brakes in a particular order? I just randomly went round them...

There is an order ..... depends how old the car is (I need Hayne's for the sequence) but it wouldn't make that much difference if you did it 'wrong' 

[tidla]

Rule of thumb is to do the furthest from the master and work to the closest.

I never put the pedal to the floor when bleeding, try to keep in the general footpedal travel range if possible.

[maracus]

Should I have bled the brakes in a particular order? I just randomly went round them...

There is an order ..... depends how old the car is (I need Hayne's for the sequence) but it wouldn't make that much difference if you did it 'wrong' 

...it's a '98

I'll have another read through mine then..

Rule of thumb is to do the furthest from the master and work to the closest.

I never put the pedal to the floor when bleeding, try to keep in the general footpedal travel range if possible.

Once there's no air present at the calipers, is it safe to assume it's out all the way through or do I need to be looking at flushing like a litre or more through the system to be double double double sure it's bubble-free?

(Admittedly I've not bled many brakes in my time but ive never had problems like this.. Makes me think the problem kinda lies elsewhere..)

[maracus]

Half sorted it; it was just me being a bit special about it I hadnt bled all the air out!

Still got to sort my abs and tc light issue and speedo, what's the general flow for fault diagnosis on this?

[RobG]

Half sorted it; it was just me being a bit special about it I hadnt bled all the air out!

Still got to sort my abs and tc light issue and speedo what's the general flow for fault diagnosis on this?

Normally knackered ABS ECU

[maracus]

Half sorted it; it was just me being a bit special about it I hadnt bled all the air out!

Still got to sort my abs and tc light issue and speedo what's the general flow for fault diagnosis on this?

Normally knackered ABS ECU

Does anyone know if the abs ecu off a pre facelift cdx is the same as on my mini facelift mv6?

[Andy B]

....
Does anyone know if the abs ecu off a pre facelift cdx is the same as on my mini facelift mv6?

Different.
Mini facelift have 4 channel ABS, earlier cars don't. 

[maracus]

....
Does anyone know if the abs ecu off a pre facelift cdx is the same as on my mini facelift mv6?

Different.
Mini facelift have 4 channel ABS, earlier cars don't. 

Darn. Are full facelifts the same or different as well? Just so I have an idea what to look for if I do need to order a new'un

[maracus]

I put my mates coder on it yesterday and it showed nothing for the abs system but threw up a couple of autobox codes, voltage low's and not present iirc, one of which something to do with injector shut off, iirc?

But anyway could this be knocking my abs etc out?

 I'll look for wire damage from little critters and see what I find though 

[Kevin Wood]

Shut-off signal is shared between ABS and gearbox ECU. Often the gearbox ECU complains about it when the ABS ECU has failed.

Did you successfully communicate with the ABS ECU and find no faults or were you not able to connect to it?

Does sound like an ABS ECU failure to me.

[maracus]

Hmm.. I'd best just man-up and replace that ecu then 

Something I'm really not pleasured by the thought of!!