P38A French CT re-test failed!

Further to my previous post about the original CT test experience. [And having replaced the track rod link arm, 4 new tyres, 4 sets of discs and pads, and adjusted the FOG light (not brake light!) beams..] My P38 (4.0l 2000) went for its CT retest last Friday.

It failed.

Again.

It failed on the brakes - according to the technician, the ABS does not work. He put the car on a 2 wheel rolling road and used some sort of electronic gizmo to enable him to test the brakes. (I think the rolling road spins the front wheels in opposite directions..is that how they overcome the need for a 4 wheel rolling road?)

He was adamant that the ABS does not work. That's all he would say.

The car gives no ABS warning light (except during the usual start up procedure), and the computer gives no ABS error codes.

I am at a loss to know where to start looking or what could possibly need fixing.

Anyone else experienced such problems.

All sensible suggestions gratefully received!

Thanks.

Was this the same place & tech that failed it last time?

Yes, same test centre/same guy. You have to take it to the same place for the re-test.

Sounds like a príck to me..

If the system hasn't logged any faults there isn't anything wrong with it.

Tell him to take it up the road and stand on the brakes..

He doesn’t like you/your Landy does he

Rollover said:

Further to my previous post about the original CT test experience. [And having replaced the track rod link arm, 4 new tyres, 4 sets of discs and pads, and adjusted the brake light beams..] My P38 (4.0l 2000) went for its CT retest last Friday.

It failed.

Again.

It failed on the brakes - according to the technician, the ABS does not work. He put the car on a 2 wheel rolling road and used some sort of electronic gizmo to enable him to test the brakes. (I think the rolling road spins the front wheels in opposite directions..is that how they overcome the need for a 4 wheel rolling road?)

He was adamant that the ABS does not work. That's all he would say.

The car gives no ABS warning light (except during the usual start up procedure), and the computer gives no ABS error codes.

I am at a loss to know where to start looking or what could possibly need fixing.

Anyone else experienced such problems.

All sensible suggestions gratefully received!

Thanks.

Click to expand...

How can you fix a fault that doesn't exist? He needs to explain why he thinks the ABS doesn't work. There must be something similar to the AA that rates garages over there and slates the duff ones? Or the government office that regulates the test centres?

Maybe send a message to @Mark Piercy and @Datatek and see what they suggest?

Sounds to me like he just wants to cost you a lot of money.
You must be able to go somewhere else, what happens if the bloke dies? He can't test it then
A 4x4 shouldn't be put on a 2 wheel rolling road and you can't test the abs of the wheels are going in opposite directions
From the owners manual;

Henry_b said:

Sounds like a príck to me..

If the system hasn't logged any faults there isn't anything wrong with it.

Tell him to take it up the road and stand on the brakes..

Click to expand...

Yes, precisely! I agree!

He did take it up the road and admitted that it seemed fine... But the computer says "NO"...

Now you begin to sense my frustration!!

Grrrrrr said:

How can you fix a fault that doesn't exist? He needs to explain why he thinks the ABS doesn't work. There must be something similar to the AA that rates garages over there and slates the duff ones? Or the government office that regulates the test centres?

Maybe send a message to @Mark Piercy and @Datatek and see what they suggest?

Click to expand...

Yes, exactly, how can I fix a problem that doesn't exist?

I was hoping that someone on the forum would come back to me and say, "oh, yes, this is a common problem - all you need to do is replace yer static sprocket flange doobry"... But evidently you all appear to be as bewildered as I am!

Rollover said:

all you need to to is...

Click to expand...

get some degreaser/kitchen cleaner, give the ABS pump a good, thorough clean, take the securing nuts off, give them a good scrub and put back. give the whole lot a rub over with an oily rag, hey presto you now have a replacement/recon unit

kermit_rr said:

Sounds to me like he just wants to cost you a lot of money.
You must be able to go somewhere else, what happens if the bloke dies? He can't test it then
A 4x4 shouldn't be put on a 2 wheel rolling road and you can't test the abs of the wheels are going in opposite directions
From the owners manual;
View attachment 218996

Click to expand...

From initial issue of a "fail" notice you have 2 months in which to rectify any problems and submit the vehicle for a free re-test at the same test centre...

Now that the 2 months have elapsed, I have to re-submit the vehicle for a new CT test. Obviously I shan't be returning to the same test centre!

I have been trying to locate a test centre that has a 4 wheel rolling road - so far without success... Rumours are that such a test centre does not exist!!

"what happens if the bloke dies"

Click to expand...

Are you suggesting that I put a contract out on the guy?

kermit_rr said:

get some degreaser/kitchen cleaner, give the ABS pump a good, thorough clean, take the securing nuts off, give them a good scrub and put back. give the whole lot a rub over with an oily rag, hey presto you now have a replacement/recon unit

Click to expand...

Excellent idea! I'll do that...it's bound to work!

RangeRoller dt said:

He doesn’t like you/your Landy does he

Click to expand...

Or he wants to own it.

Rollover said:

From initial issue of a "fail" notice you have 2 months in which to rectify any problems and submit the vehicle for a free re-test at the same test centre...

Now that the 2 months have elapsed, I have to re-submit the vehicle for a new CT test. Obviously I shan't be returning to the same test centre!

I have been trying to locate a test centre that has a 4 wheel rolling road - so far without success... Rumours are that such a test centre does not exist!!

Are you suggesting that I put a contract out on the guy?

Click to expand...

I've not heard of a 4 wheel rolling road, the usual tool is a Tapley decelerometer, which is a box you place in the vehicle and perform a moving brake test
https://www.prosol.co.uk/product/tapley-electronic-decelerometer-mts-connectable-dvsa-approved/
"It is portable, lightweight and easy to use and is a must have for most 4×4 vehicles."

as has been said before, brakes are tested, ABS is not. The only check is dash light function

Rollover said:

Yes, exactly, how can I fix a problem that doesn't exist?

I was hoping that someone on the forum would come back to me and say, "oh, yes, this is a common problem - all you need to do is replace yer static sprocket flange doobry"... But evidently you all appear to be as bewildered as I am!

Click to expand...

"Oh yes, this is a common problem - all you need to do is replace yer froggy tester"

There could maybe, possibly be a problem we are unaware of (as unaware as the tester guy ) but judging from your last thread I’d say he’s being funny.
Over here you sometimes have to explain the abs light doesn’t go off with ignition but when moving but not normally an issue. My guy is a Landy guy so I never have the hassle he understands himself

Your ABS light does go out @ xx kph?

Only option I see is go somewhere else or ask him how much to fix and pay his extortion racquet

You dont have none standard wheels and tyres fitted by any chance do you?

I dare say the ABS ECU is as confused as hell with one wheel going forward, one going backward, and the two rear wheels not going round at all. What does he expect the ABS to do in that situation? Since you say it seems to work on the open road, then the answer is - it's fine. I suppose you could go and find a skid pan to see if it's responding, and have a bit of fun while you're at it.

It's probably completely unnecessary, but might be worth going round all your sensors, cleaning/ freeing them, and then pushing them back home to reset the gap- not hard, and you don't need the wheels off

Tapley meter