ncooper:
Scania and Volvo, for example, have no air pressure in the yellow line when the hand brake is on,
therefore connecting the yellow line has no effect on the trailer brakes.
well you learn new something everyday
OVLOV JAY:
The only way you could be killed if the trailer brake is off, is if you’re dumb enough to leave the hand brake off inside the unit.
A bloke I worked with his brother was killed split coupling a fridge trailer, the sliding fifth wheel was set on the front position, he reversed under the trailer but stopped short of connecting with the pin, unit handbrake on, connected red line, trailer rolled forwad pinning him between unit and fridge unit, he had not checked trailer park brake but unit hb was on
Big Joe:
OVLOV JAY:
The only way you could be killed if the trailer brake is off, is if you’re dumb enough to leave the hand brake off inside the unit. And before you all get your knives out, yes I’ve left the hand brake off once. I was a ■■■■ for doing it and was very lucky it was on level ground and I was soloIf the fifth wheel is supporting the weight of the trailer when split coupling, there is a danger that when the red air line is connected it can roll forward when no trailer h/b is applied, not a good scenario on fridges where the motor box runs inches from the rear of the cab
so always yellow line on first
The answer there is to keep unit suspenion down when you’re connecting the suzi’s, then the trailer is still on legs, take a hell of a momentum to move it then 
When we were aloud to split couple, we were told, unit suspension all the way down, under trailer, connect lines, in unit, suspension right up and then finish hooking up.
BUT, you still have to make sure the trailer brake is ON, otherwise you can shove the trailer back into something when hooking up and also the tug test wouldn’t work.
So, whichever way you do it, you should still be checking the trailer brake 1st. And you can’t assume that the previous driver would’ve applied it because, as I said, it might’ve been shunted since then, and shunters are notoriously a lazy bunch lol
Big Joe:
ncooper:
Scania and Volvo, for example, have no air pressure in the yellow line when the hand brake is on,
therefore connecting the yellow line has no effect on the trailer brakes.
if connecting the yellow airline has no effect on the brakes. then how the hell do the brakes work?
limeyphil:
Big Joe:
ncooper:
Scania and Volvo, for example, have no air pressure in the yellow line when the hand brake is on,
therefore connecting the yellow line has no effect on the trailer brakes.
if connecting the yellow airline has no effect on the brakes. then how the hell do the brakes work?
Off the foot brake (aka the service brake), maybe that’s why it’s known as a service line?
He only said with the handbrake
limeyphil:
if connecting the yellow airline has no effect on the brakes. then how the hell do the brakes work?
There is pressure in the air line when you press the foot brake, just not when the hand brake is applied.
Paul
so what you’re saying is the handbrake only works the unit brakes, but not the trailer brakes?
triple-tango:
Twice this week I’ve had to collect a trailer, on both occasions the brake trailer brake hadnt been applied…
you’ve never done ferry trailers out of Felixstowe (and probably most other ports) then? The first place trailer brakes have been compulsory to use when dropping trailers in my 23years driving is where i started working a yr and a half ago.
repton:
The only time I ever worry about it is if I am split coupling
Where I work, they will sack you on the spot for doing that
limeyphil:
so what you’re saying is the handbrake only works the unit brakes, but not the trailer brakes?
On some units, yes.
Paul
repton:
limeyphil:
so what you’re saying is the handbrake only works the unit brakes, but not the trailer brakes?On some units, yes.
Paul
something i’ve never come across, in fact it sounds prety unsafe to me.
in light of what you’ve said, i think you’re mistaken.
limeyphil:
something i’ve never come across, in fact it sounds prety unsafe to me.
in light of what you’ve said, i think you’re mistaken.
I’ve only ever come across it on Volvos. One place I used to do agency work had a fleet of a dozen or so 04 plate FM12 units and none of them had any air pressure in the yellow line when you were coupling them up. I’ve never driven a Volvo unit anywhere else though so I don’t know if it was peculiar to their fleet or a general Volvo thing although ncooper’s post earlier in the thread suggests it is common to other Volvos (and Scanias).
Paul
commonrail:
…if someone has pressed the shunt button,will it roll forward and squash me
Isn’t the shunt button next to the trailer brake button? Is it worth making sure the shunt button ISN’T engaged when you are making sure the brakes ARE engaged?
Or does it not matter because even if you have pressed the shunt button and then disengaged it it still affects the trailer until xyz or whatever?
I’ve got my C+E but I’ve not driven one in service yet. But I am sure there are plenty of knowledgeable drivers here who can put me straight on the above without taking the [zb] 
it sounds more like a fault.
when you do an mot. you would check the foot brake operation, and handbrake operation sepperately. and both had to operate the trailer brakes.
Saratoga:
commonrail:
…if someone has pressed the shunt button,will it roll forward and squash meIsn’t the shunt button next to the trailer brake button? Is it worth making sure the shunt button ISN’T engaged when you are making sure the brakes ARE engaged?
Or does it not matter because even if you have pressed the shunt button and then disengaged it it still affects the trailer until xyz or whatever?
I’ve got my C+E but I’ve not driven one in service yet. But I am sure there are plenty of knowledgeable drivers here who can put me straight on the above without taking the [zb]
you can’t push the shunt button in when the trailer brake is applied. it will just pop straight back out again.
limeyphil:
it sounds more like a fault.
when you do an mot. you would check the foot brake operation, and handbrake operation sepperately. and both had to operate the trailer brakes.
When a trailer is MoT’d the hand brake operation is tested by using the button on the side of the trailer. At least that’s how it was tested both times I have put my bulker through a test.
Paul
So when you artic drivers approach a trailer to hook up, are you saying that you don’t do a walk around check of the trailer before you even start to hook up? That was where my trainer told me I should have checked the brake was on?
Saratoga:
So when you artic drivers approach a trailer to hook up, are you saying that you don’t do a walk around check of the trailer before you even start to hook up? That was where my trainer told me I should have checked the brake was on?
that’s about right. 
repton:
limeyphil:
it sounds more like a fault.
when you do an mot. you would check the foot brake operation, and handbrake operation sepperately. and both had to operate the trailer brakes.When a trailer is MoT’d the hand brake operation is tested by using the button on the side of the trailer. At least that’s how it was tested both times I have put my bulker through a test.
Paul
What Paul says for MOT, trailer service brakes are roller tested off the foot pedal, trailer handbrake button is popped to test parking brakes. Must admit I’ve driven Scannys and Ovlov’s and never realised the handbrake never braked the trailer Merc’s definately apply the trailer service brakes when parked, as we have to pull the yellow line off when doing brake maintenance on the trailer.
I was always under the impression that C&U regs demanded at least 50% of axles on a vehicle were braked off the park valve 
.
repton:
limeyphil:
it sounds more like a fault.
when you do an mot. you would check the foot brake operation, and handbrake operation sepperately. and both had to operate the trailer brakes.When a trailer is MoT’d the hand brake operation is tested by using the button on the side of the trailer. At least that’s how it was tested both times I have put my bulker through a test.
Paul
On Mot you check the secondary brake in the cab for the trailer which is operated by your handbrake, a trailer has it’s own parking brake, ratchet or anchor lock.