NCT report lists Parking Brake Performance at just 19% !!

peking97

Report says 19% for parking brake performance but electronic brake unit was replaced by main dealer a couple of months back at a cost of about €1000!

Should I get back to the dealer or am I mis-understanding the result? (Was expecting close to 100%).

TIA

Whocare

Think that about Normal reading of about that. Always thought it was low but all different car over years reading low enough

kirving

The % figure is a proportion of total vehicle weight, but I'm not sure how they can always apply the same force to the pads (via handbake or footbrakes).

https://www.ncts.ie/media/z55p1lpj/vir.pdf

https://www.ncts.ie/media/aidher01/nct_manual_2023.pdf

greasepalm

Does your car hold on a steep hill?

When we were doing NCT checks wheels off the ground we would check if wheel locked stop turning when applied and if wheel turns something is not right.

Also depends how good rear discs are and pads not seized in the carrier.

Is your car one that has to be adjusted if doing a brake service?

What make of car?

Padre_Pio

https://www.boards.ie/discussion/2058363547/nct-report-lists-parking-brake-performance-at-just-19

The % value represents the ability of the brakes to stop the vehicle. They use a rolling road to calculate braking force by measuring vehicle weight and torque and speed at the wheel.

Your handbrake is designed for when the car is stationary, and needs a fraction of the braking force the service brakes use, so the value is small by comparison and the pass criteria is 16% compared to 55%.

But you're fairly close to failing at 19%, I'd be asking if they can adjust the cable tension, else you may fail in a few years time.

peking97

https://www.boards.ie/discussion/comment/122481912#Comment_122481912

Car is Renault Laguna III 2011 (Initiale Paris edition) which I've had from new. Don't think there is any adjustment possible.

Looking back over previous NCT reports I see that parking brake performance peak was 39% back in March 2019.

Will get the rears looked at even though rear discs/pads replaced Sept' 2022.

kirving

https://www.boards.ie/discussion/comment/122482066#Comment_122482066

How do they know how much force is being applied by the tester, in the case of a manual handbrake? Or do they just keep pulling until they hit 19%?

greasepalm

Make sure they are 100% pads are not rusted into their carriers as sometimes when removed they needed to be filled down to allow easier movement.

Users car is Electronic brake hold.

Trying to remember if that has the unit in the center rear and handbrake cables going to each side to caliper.

Caliper slides should be free also or wont get the full effect of a clamping motion on the pads and will wear at an odd angle.