RWD3M
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I'm fairly sure I have no idea what you're talking about. If it's a parking brake, then why do you think it's a 'secondary braking system', meant to stop a 2 tonne brick?!
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Any vehicle that has a dual master cylinder/twin line braking system (i.e. any car since some time in the 70s IIRC), doesn't use the parking brake as a secondary braking system.
roblane65
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Are people talking at cross purposes here ? Hand/park brake or park in an auto box which isn't a brake . The hand /park brake apllied to a set wheels cannot use the same system as the main brakes { I.e. the same hydraulic system ) does he not mean secondary as in the fact if the main brakes fail the hard /park brake can still be used regardless . the hand /park brake still has to pass a test regardless of the weight of vehicle be it a 1/2 ton mini or 2 3/4 ton range rover
Wedg1e
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I was thinking that if the autobox can lock the vehicle securely parked, why does it matter whether it even has a 'parking brake' on the wheels?
Obviously you can't use the autobox Park as an emergency brake, threfore you need a secondary braking system, independent of the main hydraulics... I just wan't sure if or how an EPB would fulfill that function since you'd think there's nothing to stop someone hitting the switch when in motion. As described by willie.macleod though, it does appear to allow that.
Wedg1e
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I realise that; however not everyone fits Brembo or top-notch brand, you assume that all makers have to meet some base standard. My point was I have seen the friction material come away under the enthusiastic application of the 'Jaguar-style' handbrake while trying to meet the efficiency test. You wouldn't want to find it doing that in an emergency - when, it would be fair to assume, you'd be 'enthusiastic' yourself.
I hate EPB's with a passion. Unnecessary tech that replaced a mechanical system that is simple & works perfectly well.... with something complex, less reliable & less easily home maintained.
I simply would not buy a car that had one while there was an alternative vehicle that didn't have one.
(Sorry, I know that's no help whatsoever to the OP
)
I simply would not buy a car that had one while there was an alternative vehicle that didn't have one.
(Sorry, I know that's no help whatsoever to the OP
)No parking brake is meant to stop a 2 tonne car (my Jag is only around 1600 kgs, Aluminium bodied), that's why they are called parking brakes and not runaway stopping brakes
ALL parking brakes are rated to stop even if not quickly in the case of a total main brake system failure.
I think the % efficiency is lower in a split brake system than a single system as with a split you have some brakes left in a failure.
Why are fog light called fog lights when they are reduced viability lights and can be used in other conditions not just fog?I'm fairly sure I have no idea what you're talking about. If it's a parking brake, then why do you think it's a 'secondary braking system', meant to stop a 2 tonne brick?!
The name does not limit its use.
Same goes for the parking / emergency brake.
If you activate the EPB switch while moving the brakes will apply BUT not stay on when you release the button.
I knowI'm fairly sure I have no idea what you're talking about.
that's why I suggest reading the MOT testing manual.MOT testing manual will tell you differently. Section 1.3.1 (secondary brake)-
This inspection is only for vehicles with a single line braking system.
keithski122
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I've seen it happen far more often in french cars on a normal handbrake system.
Old Citroën Zantia's?
The front wheel h-brake on those meant the discs cooled when parked & the h-brake grip eased off.
Apparently it wasn't uncommon for owners (who parked on a slope out of gear) to find their car at the bottom of the hill (or "resting" on the car below it) when they returned
roblane65
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I had similar happen to an Iveco daily ! It was six weeks old rolled across the road and smashed into a skip corner of the skip into the center of the back doors , good job it was only about 15 yds though my house is two thirds the way up a fair bank ! . Any how the Iveco garage came and took it straight to a test center and said brakes were in tolerance , well big thick solid discs and a crappy cam system with hardly any movement meant exactly the same as above great when the discs were hot But it wasn't when they cooled 
It wasn't the only time it happened either . Never left out of gear after the second occasion , I was working in a front garden and saw it start to roll after it had been parked up about twenty minutes . That van had 5 rear calipers while it was under warranty .
It wasn't the only time it happened either . Never left out of gear after the second occasion , I was working in a front garden and saw it start to roll after it had been parked up about twenty minutes . That van had 5 rear calipers while it was under warranty .
Wedg1e
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The 'wedgy' Austin Princess had a pretty funky braking system: each front caliper had 4 pistons in two pairs with separate fluid circuits.
One pair of pistons in each each caliper were linked to a pair on the other as well as one of the rear calipers, the other pairs were linked to each other and the other rear caliper, there was a pressure imbalance detector and a monstrous master cylinder with separate fluid chambers... shame they wasted it on the Austin Princess
Those calipers were beloved of 'fast Ford' owners as they'd bolt straight onto the Ford bracketry and give 4-pot 'power'... albeit probably wasted as the Princess pads are smaller than some of the Ford ones and in some cases overhang the Ford disc so lose contact area.
One pair of pistons in each each caliper were linked to a pair on the other as well as one of the rear calipers, the other pairs were linked to each other and the other rear caliper, there was a pressure imbalance detector and a monstrous master cylinder with separate fluid chambers... shame they wasted it on the Austin Princess
Those calipers were beloved of 'fast Ford' owners as they'd bolt straight onto the Ford bracketry and give 4-pot 'power'... albeit probably wasted as the Princess pads are smaller than some of the Ford ones and in some cases overhang the Ford disc so lose contact area.
Wedg1e
They call me Mr. Bodge-angles
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My ex-wife (well, one of them) had a Xantia; I don't recall a problem with the brakes but then she wrote the engine off by not telling me about the flashing oil level warning light before it threw a rod through the front of the block.Old Citroën Zantia's?
The front wheel h-brake on those meant the discs cooled when parked & the h-brake grip eased off.
Apparently it wasn't uncommon for owners (who parked on a slope out of gear) to find their car at the bottom of the hill (or "resting" on the car below it) when they returned
The EPB system does function as an emergency brake if you pull and hold the switch when moving. That makes it work with the main braking system to perform an emergency stop, as I discovered in my old XFR one day, quite by accident. Caught the switch by accident and almost soiled myself at the resulting emergency stop.
It’s the same system as fitted to LR products, and there is also a set and bed-in procedure which involves performing this kind of stop from 12mph. That is more for the systems like Discovery 3 where the park brake is shoes inside the rear disk. But it was part of the R type parking brakes as well, those which had separate calipers for the handbrake and service brake. The S-Type R was a real pain to get them set properly.
As for the switch problem, is it the switch? Or could it be the EPB unit itself? Those are known to do a screamer sometimes which results in having to remove it, replace any damaged gears, rewind the cable and refit it. Or get a refurb one exchange.
Do you know anyone with Bosch VCATS? That’s the diags the factory uses and has reset routines for the EPB.
It’s the same system as fitted to LR products, and there is also a set and bed-in procedure which involves performing this kind of stop from 12mph. That is more for the systems like Discovery 3 where the park brake is shoes inside the rear disk. But it was part of the R type parking brakes as well, those which had separate calipers for the handbrake and service brake. The S-Type R was a real pain to get them set properly.
As for the switch problem, is it the switch? Or could it be the EPB unit itself? Those are known to do a screamer sometimes which results in having to remove it, replace any damaged gears, rewind the cable and refit it. Or get a refurb one exchange.
Do you know anyone with Bosch VCATS? That’s the diags the factory uses and has reset routines for the EPB.
keithski122
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Both citroens and peugeots, with rear wheel handbrakes, unfortunately not seperate handbrake shoes so its the main brakes.Old Citroën Zantia's?
The front wheel h-brake on those meant the discs cooled when parked & the h-brake grip eased off.
Apparently it wasn't uncommon for owners (who parked on a slope out of gear) to find their car at the bottom of the hill (or "resting" on the car below it) when they returned
