Brakes: 2009 xc90 parking brake MOT

[minstrelblue]

hi, i understand they don't use rollers for 4x4 on MOT's but use a decelerometer, but last year the MOT tester did a rolling road test for my parking brake and then promptly failed it. i said that was bonkers cos that's not designed for that, it's a heavy vehicle and the parking brake on the drum is small and only designed as a parking brake not to slow it down at 30mph!!!, nevertheless it cost me a hundred quid to strip them down despite them working well when parking as it is designed for. so my question is.. is it right for an mot to test a xc90 parking brake on the move

[Harley Dave]

As usual, Google is your friend (or not...)

http://www.ukmot.com/manual/3.1/Parking-Brake-Control

Cheers

Dave

[Father Ted]

So, reading this, with a foot operated parking brake, it doesn't require testing on a rolling road.
That's interesting.

Another question: With these being "permanent" 4wd, can the brakes be tested on rolling road, or do they have to use a decelerometer?
My last 4wg (Toyota Estima) had to use the decelerometer, but that was a more primitive 4wd system.

[Tannaton]

Any post 2003 AWD Volvo model should be tested on a rolling road at MOT, there is no reason for it not to be. For some reason many MOT testers don’t seem to understand how to determine the drivetrain type.

I had my 08 XC70 tested last weekend and I almost had to beg the tester to put it on the rollers - my wife drives that car and I wanted to know that all four corners were braking as they should.

The only cars that can’t be tested on the rollers are thermo viscous coupling AWD cars which include Freelander Mk1 and pre-2003 model year Volvo.

To the OP yes it is correct that the parking brake is tested on the move. It’s is a big, heavy car all the more reason it needs a good parking brake. The pass level for the decelerometer test is way below what a good, working XC90 parking brake should achieve.

[Clan]

Originally Posted by minstrelblue

hi, i understand they don't use rollers for 4x4 on MOT's but use a decelerometer, but last year the MOT tester did a rolling road test for my parking brake and then promptly failed it. i said that was bonkers cos that's not designed for that, it's a heavy vehicle and the parking brake on the drum is small and only designed as a parking brake not to slow it down at 30mph!!!, nevertheless it cost me a hundred quid to strip them down despite them working well when parking as it is designed for. so my question is.. is it right for an mot to test a xc90 parking brake on the move

You can test the parking brake on the rollers up to 2007 models but after that they had "Instant Traction" which means all 4 wheels drive up to about 10 mph to help getting away from rest.

which ever method is used they are testing for an efficiency of at least 16% which isn't that good , older cars with single circuit brakes are tested to 25% for the parking brake ...

[Tannaton]

Originally Posted by Clan

You can test the parking brake on the rollers up to 2007 models but after that they had "Instant Traction" which means all 4 wheels drive up to about 10 mph to help getting away from rest.

which ever method is used they are testing for an efficiency of at least 16% which isn't that good , older cars with single circuit brakes are tested to 25% for the parking brake ...

Hi Clan, I thought The instant traction feature was only operational when the car was moving under its own power - ie in drive and throttle applied? My 08 XC70 sat on the rollers without issue during its test last week?

**EDIT: Mine is a early P3 XC70 with Gen3 Haldex (they changed to Gen4 in MY 2009 for the P3) but I believe that was the generation when "instant traction" was introduced?

[Barnacle58]

All you could possibly want to know courtesy of SwissXC90

https://www.volvoforums.org.uk/showthread.php?t=279043