UMD V3 Installation Manual - Remote Control
13 November 2018
Page
15
of
39
Diagnostic Tests:
Testing the Fridge Interface:
After the UMD / Carrier Fridge interface cable is connected to the 3 way flat connector in the Carrier fridge
loom, with the fridge OFF, measure the resistance between the chassis (0V) and Pin 3 of the plug that will
connect into the UMD COM2 Port. This should be <10 ohms. If this is not correct, check the wiring of the Flat
Carrier loom plug back to the Fridge Controller. Turn the fridge ON and measure the voltage between the
chassis (0V) (negative of meter) and Pin 2 of the plug that will connect into the UMD COM2 Port. This should
be
–
8 to
–
10V DC. If this is not correct, check the voltage on Pin 1 of the same plug. If that is
–
8 to
–
10V DC
then the wiring to pins A & B of the carrier flat loom plug need to be swapped and the measurement re-taken.
If there is no voltage present on either pins 2 or 1, check the connections from the Carrier loom flat plug back
to the fridge controller.
Picture 12: Cooltrax Interface Plug
If these two measurements are correct, connect the fridge interface cable to the UMD COM2 Port and power
ON the UMD (If not already ON).
If the Fridge cable was connected to a UMD that was OFF and then powered ON after the connection was
made, the UMD should sense the fridge within a couple of minutes and the fridge light on the UMD should
come ON RED.
Picture 12: UMD LED’s
System Test:
1.
Check the Engine Bay for any tools, fixings or off-cuts, which may have been left behind.
