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Hi there,
I've just had my warrant of fitness done for my car and I noticed something strange.

I usually take my car for inspection at the govt testing station (Waitakere Testing Station) , and they way they record the brake tests results are for each side ( 100%, 100%, 90%, 90% respectively).

But just for this time I was experimenting using the local garage instead. And in the checklist, they didn't fill out the 4 boxes corresponding to all 4 sides, but instead in the middle they put "68%"
Is this acceptable and will i have to replace my pads soon ?

Also, could you educate me abit on what brake blending and brake bleeding is ?
I was notified by the inspector that this might be needed because there is a bit of air in the brakes and also needs to top up brake fluid.

As far as I know, brake fluids aren't consumed unless there is a leak ?

Thanks in advance.

The reason for the difference in readings is due to different testing methods. Testing stations use brake rollers which are set into the ground and can test each wheel individually. Smaller garages use a machine called a Tapley Meter, which sits on the floor of the car. The car is driven on the road and when the brakes are applied, it measures the rate of deceleration.
Neither testing method can tell if the brake pads are getting worn, as brake pads will still perform efficiently even when they are wearing low. Hence the importance of servicing, as the brake pads can often only be inspected during a service by removing the wheels.
When the brake pads wear down, the caliper pistons expand out, so the fluid level will drop due to the additional fluid in the caliper cylinder. This is likely to be the reason your fluid level has dropped.
Brake bleeding is required when there is air in the hydraulic system. Unless there's a problem, air will not enter the system, so it shouldn't be necessary to bleed the brakes. However, brake fluid should be replaced at regular intervals, at which time the system is bled. Again, this comes down to proper servicing and maintenance.
It sounds like your brakes are working fine but perhaps your pads are getting low and will need replacing soon.

Thanks for the thorough reply. Much appreciated.

Does this mean that if there is even abit of air , there's a serious problem / leak with the braking mechanism ? Or just simply because the pads are wearing and fluids are coming down ?

The dealer that I got it from did tell me that it most likely have been sitting in Japan + port + ship for quite a while before it got to the yard.

As the car passed the WoF I'd say it's unlikely that there's air in the system and more likely that the fluid level is low due to worn pads.
However, brake fluid is hydroscopic and can cause corrosion in the brake cylinders and lines if it is not changed regularly. If the car is a recent import with no service history, a full service would be recommended, including checking the brake pads and replacing if necessary, and changing the brake fluid.

Hi ABayliss,

To follow up on this,
Yesterday I got my car re-inspected at VTNZ (wof) , just for my peace of mind since I don't trust the small garage that did the previous WOF.

It passed..but ...the brake readings are like this:

FL/FR: 220% , 220%
RL/RR: 130%, 150%

parking brake : 120%, 140%

I got no warning though.

If the garage previously did the brake bleeding + topping up fluid , could this be a problem with the percentage indifference? I understand 20% is the max threshold allowed ?

The car doesn't pull to one side though.

Should I be concerned ?

With the rear readings being slightly imbalanced on both the foot and hand brake, I'm assuming this car has drums on the rear. In that case, it's possibly just a slight adjustment required, although it's not always possible to get them exactly even.
The readings are within allowable tolerance and will stop the car good and straight. So basically, there's nothing to be concerned about.

Cheers thanks!