10
AU
Freephone
1300 538 598
E
www.trailparts.com.au
Troubleshooting
Fault
Possible Causes
Repairs/Checks
In-cab controller shows
‘Low Trailer Battery’
warning (old style In-cab
Controller shows Eb Error)
Or
No tail lights / tail lights
go out when brakes are
applied.
In-cab controller shows
‘Please Drive with Your
Headlights On’ message,
even though the headlights
are on
(old style In-cab shows Ec
Error).
Battery is excessively
discharged.
Bad connection between
trailer mounted brake
controller and battery.
Blown battery fuse.
Poor connection on battery
terminals.
Serial number mismatch
between Controller and
Trailer.
Faulty trailer plug
In-cab controller cannot
communicate with the
trailer mounted controller
due to interference
Incorrect wiring by-passes
controller.
Poor connection on battery
terminals.
Check battery is over 12.5V when
disconnected. If lower replace the
battery.
Check if battery is charging by
disconnecting the battery leads,
connect to vehicle and switch
lights on. Then check for 14V on
the end of the battery leads. A
measurement of 14V means the
charger is working – if no voltage
then a replacement or repaired
controller is required.
Check leads, fuse holder and any
connections between the battery
and controller for
poor / corroded connections. Any
high resistance joins will cause
excessive voltage drop to the
controller under braking resulting
in the ‘Low Battery’ error.
Obtain serial number: Refer to
page 19
If they do not match then follow
instructions on page 16/17.
Check trailer plug pins are not
corroded or crushed in, and either
spread the pins, remove corrosion
or replace the plug.
Check the controller to In-cab
connection by taking the in-cab
unit back to beside the trailer
mounted controller, if still error is
still present controller needs to be
replaced or repaired.
Check the vehicle connection
goes to only the trailer mounted
controller and all tail and marker
lights from the controller lights
output.
