Went down to the ACC ( co-op ) depot at
Halesowen yesterday with my usual Scania 420
pulling reefer trailer.
Halesowen is made interesting by being a blind
side reverse onto bays angled with concrete walls
either side.
All of our trailers are tri axle with rear steer axles.
Usually check the trailer when i couple up and
make sure the switch for the rear steer is forward
to lock out the steered axle.
Trailer yesterday didnt have this switch so thought
nothing more of this.
drive to Halesowen - A1-M18-M1-A42-M42
back up M5 to junction 3, went ok.
Got ready to back onto bay and asked a couple of
drivers to watch my back.
Started to reverse and someone shouts your rear steer
is still on your trailer.
Every one looks for switch until someone says are
your revering lights working on your
tractor unit.
It seems when you select reverse electrics sense
your reverse lights on your unit coming on and send a signal
to trailer to lock out rear axle steer.
Apears fuse had gone and tractor reverse lights were,nt working
so rear steer on axle was staying on.
Replaced fuse but was so chewed by then :
raining heavy,warehouse staff coming up to dinner
asked a driver to put it on bay for me.
Now know to check reverse lights on unit before i
leave yard.
P.S. like i said before never be afraid to ask other drivers
for help.
it takes a bigger man to ask for help than not ask
and cause damage to unit or innocent bystander.
P.P.S. those people learning to drive enjoy
having someone sat next to you.
It becomes a different world when you are on your own.
but i enjoy the good and the challenges - definitely.
A common problem.
These work by having an actuator (or solenoid - can’t remember which} which pushes a pin through a hole to lock the axle. The trailer needs to be ‘straight’ before the holes line up.
For future reference, carry a bolt, about 12 mm thread diameter, because there are usually another set of holes that you can use to lock the steering manually. Be sure to remove it afterwards otherwise the turning arc of the vehicle will be outside the limits defined in Con & Use Regs.
Otherwise, just dump all of the air out of the trailer suspension. That’ll also keep it straight. I don’t fully understand how this works, but it does. 