Log in

View Full Version : Testbook T4 & IIDTool Brake bleed procedure, differences ?



haydent
30th July 2022, 12:38 PM
Hi, Im hoping someone has some experience with a T4 on D3/D4/RRS and the assisted brake bleed procedure.

I have a RRS and IIDTool

In the workshop manual as most would have seen/heard it says to bleed from furthest wheel to closest of the abs unit.

With the feature in the IIDTool, it gets you to do in this order: Rear Left, Front Left, Front Right, Rear Right
With the last 2 wheels including abs pumping procedures.

I didnt understand the logic to this, so contacted them, they said at first that my confusion was that they make the app to suit the NA (american) market cars (LHD) , but that still doesnt match up with the manual.

When I mentioned this they said they just copied the order from the T4 procedure...

This I cant know about, so does anybody here ??

I would have thought it would make more sense to do the 2 rear wheels first then the front, with the electronic pumping on the 2 front wheels ? Though I know the brake reservoir is divided into 2 halves for redundancy, and maybe the carries on in the abs pump, so there needs to be an electronic purge for front and back sections but not left right ??

josh.huber
31st July 2022, 04:25 AM
Hi, Im hoping someone has some experience with a T4 on D3/D4/RRS and the assisted brake bleed procedure.

I have a RRS and IIDTool

In the workshop manual as most would have seen/heard it says to bleed from furthest wheel to closest of the abs unit.

With the feature in the IIDTool, it gets you to do in this order: Rear Left, Front Left, Front Right, Rear Right
With the last 2 wheels including abs pumping procedures.

I didnt understand the logic to this, so contacted them, they said at first that my confusion was that they make the app to suit the NA (american) market cars (LHD) , but that still doesnt match up with the manual.

When I mentioned this they said they just copied the order from the T4 procedure...

This I cant know about, so does anybody here ??

I would have thought it would make more sense to do the 2 rear wheels first then the front, with the electronic pumping on the 2 front wheels ? Though I know the brake reservoir is divided into 2 halves for redundancy, and maybe the carries on in the abs pump, so there needs to be an electronic purge for front and back sections but not left right ??

I'm not sure about what T4 means, but if you're changing fluid, generally no tool needed, start where you want etc, however best practice Dictates what you said above, rear wheels first to get most of the fluid then fronts. I use different branded fluids each time so it changes colour and I can see the new fluid come through.

If your bleeding because you changed a master cylinder etc.. You need to use the tool to activate the ABS pump to purge it. On older cars then still do rears then fronts.. But my understanding was with traction control and stability control all coming from the ABS unit, is that it's individual lines to each wheel from the pump now, so the old method is redundant. As in older systems the rear wheels were engaged together if one locked.

What's t4 mean

haydent
31st July 2022, 04:39 AM
testbook t4 is genuine computer diagnostic tool landrover mechanics have to for example activate abs pump procedure.

josh.huber
31st July 2022, 06:14 AM
testbook t4 is genuine computer diagnostic tool landrover mechanics have to for example activate abs pump procedure.

Cool. That's my something new for today.

Cambo_oldjaguar
31st July 2022, 08:22 AM
T4 is the old dealer/factory diagnostic tool for Land Rover (was also a version for MG Rover) I have one.

https://uploads.tapatalk-cdn.com/20220730/3d441537b37d678966ad967d642c6d5c.jpg
https://uploads.tapatalk-cdn.com/20220730/3231d08be6d1ee587f46e7983f757f8b.jpg
https://uploads.tapatalk-cdn.com/20220730/2de15789bf3f3b8f73612795363c64c6.jpg

But it never supported the L319 D3, it only did the old vehicles, like L318 D2 and the L322's up to 2004, with some limited functionality in the L322's up to 2006 with BMW driveline.

L319's were only ever supported by the new at the time IDS diagnostic tool, which later became SDD.

Some internal documents from the early days of the L319 refer to T4, but it was never applicable.

So either he's copied stuff from the T4 that is old or wrong, or he's taken it from IDS/SDD and calling it T4 for some reason or another.