Mgzt-t brakes
 

Hi There, when bleeding my brakes on my mgzt do I have to use one of those T4 gadgets? I've bled brakes but still sinking and a mechanic said the abs module is knackered. Would it be knackered or is it I have to use a T4 gadget tool to do it? Can any one advise me please it's doing my head in.

From what I understand, you can bleed the brakes without a T4 providing you don't turn on the ignition at all while doing so.

You can providing air doesn't somehow work it's way back up to the ABS pump.

I guess it depends on what effect you have. Search term 'SPP' (Sinking Pedal Phenomenon) discusses a sinking effect that's common to many cars, including Jaguars. It's not a fault, nor an MOT issue and is well known to MOT testers.

More here: https://cse.google.com/cse?cx=013872...29.BtyUrFGVY5s

Interestingly, the RAVE manual doesn't mention T4 even for fitting a new, empty ABS unit. It is mentioned apparently, in guidance presented 'outside' the RAVE documentation. I've never seen this info and the essence of it has never been demonstrated - to my satisfaction anyway. The T4 manual does contain a routine for opening the ABS unit's internal valves when brake bleeding. What's for sure, the vast majority of 75/ZT bleeds are done using the well trodden methods.

TC

I found this post using the search when my interest was piqued, I hope it is useful


https://www.the75andztclub.co.uk/for...d.php?t=304036

The 'gravity' method works in exactly the same way as any other method. The only difference is in the pressure difference between the level in the master cylinder and the bleed nipple. The 'head' of fluid provides the lowest difference possible, so is the slowest method possible. Other than that, it's identical to 'pressure' bleeding and 'vacuum' bleeding. They're simply different ways to create a differential pressure which moves the fluid. You could get an even slower flow by driving the car up a mountain to bleed the brakes. Alternatively, it would be slightly faster if you went into Death Valley to do it.

As noted in the cited thread, the relevance of a T4 is not explored,. On the other hand, gravity is great for a paraphernalia-free, single-handed brake bleeding experience. You can read your favourite book at the same time.

TC

How will that happen Jamie? it is my understanding that the default for the ABS system is for the valves to be closed.


I would have thought it would need some other outside intervention to allow air to enter the pump.


So that aside, for the benefit of the original poster, how does T4 interact with the ABS pump to allow bleeding to take place more successfully?


When I replaced the pipework on my own car recently, I used a Gunson Easybleed, and didn't seem to suffer the problem of a sinking pedal, I'm curious as to what may have cause the issue on this chap's ZTT

This thread is well worth reading through for anyone whom is going to bled there brake or change the fluid.

https://www.the75andztclub.co.uk/for...ad.php?t=63314

read Jules replies.
https://www.the75andztclub.co.uk/for...=63314&page=13