Shock, Horror ... driving home and felt spongy pedal then three lights on the dash and suddenly, no brakes.

Managed to miss the car in front and the missus managed not to have kittens.

Fluid is full - now to overflowing due to a pitch dark top-up.

So, Modulator, pump or accumulator or, of course, all three.

Can anyone point me to a simple test procedure to isolate the fault.

All help gratefully received.

CJ ...

 

No brakes kind of sounds like a broken brake line. I think if the pump/accumulator had a problem, you would lose your ABS but still be able to stop. Are you sure you have NO brakes and not just rear brakes.

 

Do you have any braking power at all? If you SMASH the pedal will it try to stop?

If you don't see any fluid leaks, and you noticed a gradual brake behavior change the past week or so. Then chances are the POS plastic piece in your modulator finally blew up. On the BOSCH models they fixed this by using a metal washer instead of a plastic one. Any GEMS model with trac control is susceptible to this failure. The official fix is usually to replace the whole modulator, which usually costs and arm an a leg. Only recently did some rover owners with access to a machine shop decide to make their own washers. They sell for around $96.00. You could have a mechanic do it, but they might not touch it due to liability. If you are mechanically inclined you should be able to do it yourself. http://www.rover-renovations.com/Bra...-p/bmr-kit.htm

 

first i would check for any visable signs of leaking at the wheels or under hood.if no leaks then turn on key and listen for the brake pump turning on.if not check power at the pump.or check for the abs pump fuse due to faulty pump.good luck

 

Hi all,

There is a bit of brake there, right at the bottom of the pedal travel. That's how, along with gears and handbrake, I managed to drive it home.

I did notice a change in the pump sound shortly before the failure and I also think the pump has been on for far too long over the past few weeks.

I'm never sure if what I can hear is the ABS pump or the EAS pump. Is there a way of determining which is on or off - perhaps a fuse that can be removed?

I have heard of the plastic washer fault and the guy in Oz that does a kit (HSE?)

I would really like to isolate the fault before I go about replacing everything under the bonnet ;o)

Thanks in advance,

CJ

 

You should still have brakes even with the abs pump malfunctioning, it just won't be power brakes. See if you can bleed the master cylinder on the modulator. If no fluid appears out of the bleed screw when the pedal is depressed, you have some sort of internal leakage. Did you hear a "whoosh" when you lost braking power by chance? I would suspect the abs pump if it didn't happen so suddenly. An abs pump malfunction is usually more gradual until nothing. Not a sudden loss of all braking power.

 

LRScott ... Thanks for the reply. I can't say that I heard a whoosh - dearly beloved was bending my ear at the time - about something trivial.

I think the brakes were going down a bit for a few days before the 'loss'. You know how it is though, you are so used to driving the beast that you adapt to it.

We had also had some snow and ice so ...

I do remember the TC cutting in a couple of times a few days previously when the weather was particularly bad. Could this have prompted a failure?

Do you know a simple way to isolate the EAS pump? According to Rave it has a couple of relays and a fuse or two. Is there one that I can pull so that I can listen to the ABS side of things?

I really am grateful for any help here. Up to my eyes in work at the moment and using the wife's Renault (Yuk!)

I'll get to the Rangie at the weekend though.

Cheers,

CJ

 

Well, you can pull the relay (idk which one it is off the top of my head) or you can just unplug the power to the EAS pump. Your ABS pump might have an internal leak preventing it from charging the system. However, I'm almost certain you will still have brakes even without the pump. It just won't be power brakes. And usually with the abs pump failing, its a gradual loss in braking power, not a sudden loss.

 

The ABS pump should not cause brake loss, it just will not work the ABS. It sounds like the master cylinder may have gone and is causing the fluid to come back in the resevoir instead of trying to push it through the lines. You will still have some brakes since the stroke will generate just enough pressure in the system but it is not reliable. I think you need to look at the master cyclinder first, if it is bad then you still will not see any leaks in the system.

Have you tried pumping the brakes to see if you can get any pressure out of it? All that a master cyclinder will do is multiply the power from the stroke to get the same amount of pressure through the lines as volume to the caliper, so obviously if it is not pushing any fluid then you have no brakes at all.

Let us know what else you find out. This may be one to take into a brake shop and see what they say.

 

Actually the pump supplies power braking to the whole system, it doesn't use the conventional vacuum powered master cylinder. Idk why they call it the abs pump, it should be called the brake pump.