I own a 1999 chariot grandis it is a import into the UK we are currently experiencing a problem with occasional seizing of the brake pedal. We are unsure if it is the servo or it is something else. ON the servo is a electrical sensor, we have spoken to a dealer near us and they couldnt help. Is their anybody that would know what this sensor is and could the problem be electrical. I would of thought that if it was the servo it would fail completey. the problem has been happening for about 5 months now and we need to get it sorted. PLEASE HELP. :57:

Hi, when you say seizing of the pedal, do you mean the brakes lock on? If it is just the pedal, is the return spring running free and operating correctly?

Further, you mention a sensor on the servo. This could be the vacuum sensor. The engine ECU monitors this sensor. There is also a fluid level sensor in the brake fluid reservoir.

Do you have any warning lights on the dashboard?

Thanks for your response, the pedal is ok. When we apply pressure to brakes on occasions you have to push down on the pedal hard to stop. We are losing assistance from the servo to do this, and then it returns back to normal. I am concerend that if it was the servo, then it would just fail completely. is it a electrical problem? We have checked the pipe to the servo and there is no leaks or splits. Would this sensor on the servo intervere with the operation of the servo unit.

I also noticed last week that if the problem occurs the power sterring becomes hard to turn just for that split secound. Are the servo and steering linked in some way or are these different issues.

Ours is a '98 but otherwise the same, we haven't noticed a problem with the brakes but do get the lack of power steering assistance for a second or so on a roundabout if it's hammering down with rain.

So far I've just assumed that the P/S belt is slipping a little, so it's possible that yours isn't linked either.

Although I wouldn't expect it to solve your problem it's probably worthwhile renewing the brake fluid unless you know it's been done in the last 18 months or so.

Normally the servo operates purely from the engine vacuum. The sensor is just that, so it would not interfere with braking efficiency unless it was leaking.

Servos do not necessarily fail completely and I can only guess that the servo is leaking and that a new one would fix it. One test you can try is to run the engine to create a vacuum in the servo, then turn off the engine. Press and hold the brake pedal and if you can hear a continuous hiss from the servo, this proves the leak theory. Normally it would just hiss once briefly if the servo were good. The servo holds enough vacuum for several brake pedal presses under normal circumstances, but if it's leaking it will run out sooner.

Power steering is a completely separate system with the only common link between the brake servo and the steering being the engine, which operates a belt to the steering pump in this case. The engine stalling would cause your condition, but I would think you would notice that.

Check the power steering belt tension which should deflect no more than 9.5-11.5mm on it's longest run under firm pressure with no A/C or 6.8-7.6mm with A/C. (If you can get near it). If it squeeks a lot or is cracked it may be slipping anyway and need a new one. Check the P/S fluid reservoir just in case you have a leak somewhere too. You need Dextron fluid to top it up.

A handy A5 size repair guide is printed by Peter Russek and you can get one on eBay.

Hope this helps.