Help needed any fitters?

UK PROFESSIONAL DRIVERS FORUMS THE UK PROFESSIONAL DRIVERS FORUM (INTERACTIVE)
1

hi one of our trucks 06 magnum has a big problem the handbrake wont relese and there is no air coming out of the suzy it builds up to 12 psi but we just cant move it it only seems to happen when the trailor it is hitched on to looses air we have spent many pounds on new parts but we just cant find the problem?

2

If its only managing 12psi id suggest looking at the compressor or the safety valve as it should be around 150-180psi at full pressure. Or if its just a typo and you ment bar then that side should be fine i know when i had similar prob on my cf daf it was the valve block behind the off side step thonk they called it an APU

3

So it’s doing the same as a Broms brake would do, there’s likely to be a valve somewhere that does the same thing as the Broms, but automatically, lack of pressure trips the valve, when you restore pressure from the other side it opens again, I’m not an expert on the Magnum (or anything for that matter :laughing: ) but if I was on the side of the road, I’d start at the parking brake valve in the cab and work my way back from there :wink:

4

Yes definitely sounds like the APU , we had a similar problem on an 06 magnum , park brake just wouldnt release , driver managed to get brake off but if engaged park brake again would stay on , i remember parking in yard on the flat and running to grab a chock of wood to make sure it wouldnt move :smiley: :smiley: , renault came and took it away and changed apu .

5

newmercman:
So it’s doing the same as a Broms brake would do, there’s likely to be a valve somewhere that does the same thing as the Broms, but automatically, lack of pressure trips the valve, when you restore pressure from the other side it opens again, I’m not an expert on the Magnum (or anything for that matter :laughing: ) but if I was on the side of the road, I’d start at the parking brake valve in the cab and work my way back from there :wink:

ye when we restore pressure to the trailor then the unit will relise whats apu thanks for replies

6

Sounds like the APM which is a complicated air dryer - take off the handbrake feed pipe (green band) and see if there is any air out of the APM - if not new APM -will need programming as its an ecu in tis own right.

Steve

7

neversweat1:
Sounds like the APM which is a complicated air dryer - take off the handbrake feed pipe (green band) and see if there is any air out of the APM - if not new APM -will need programming as its an ecu in tis own right.

Steve

APM thats the one i meant :wink: