11
NZ
Freephone
0800 487 245
E
www.trailparts.co.nz
Fault
Possible Causes
Repairs/Checks
Brakes randomly come on
and lock up.
Braking output on In-cab
controller stays at ‘-‘ on the
screen when brakes are
applied.
In-cab Controller shows ‘0’
or higher numbers when
brakes applied but no
braking happens.
Faulty Break-away switch.
Faulty Break-away wiring.
In-cab controller has
‘emergency stop’ button
pressed.
Faulty trailer plug / vehicle
connection.
Incorrect wiring bypasses
controller.
On electric drums – Faulty
wiring or magnets.
On hydraulic actuator driven
brakes – Faulty wiring or
isolator if fitted
Check breakaway switch and
wiring for a short circuit. Replace
any faulty components or wiring.
Make sure In-cab controller is
securely mounted on vent holder
and emergency stop button not
inadvertently pressed.
Check and repair trailer plug and
vehicle socket and associated
wiring – replace any faulty parts.
Check vehicle connection goes
directly to the controller and does
not bypass the controller.
On electrics check wiring
and drum magnets for faulty
connections. Normal magnet
resistance is 5 Ohms. 2 Magnets
together is 2.5Ohms and 4 is 1.25
Ohms.
On Hydraulic the Blue signal wire
should be checked for voltage
when the emergency stop being
is pressed. If there is some voltage
and there is no brakes then call for
assistance.
