Taylor-Dunn B0-T48-48 Taylor Truck T48 Operation Manual page 123

TEST 7.3:
If the vehicle does not travel in forward, skip
ahead to test #7.4.
Place the forward and reverse switch in the
REVERSE position.
Referencing battery positive, test the voltage at the White/
Black wire on the F&R switch.
If the voltage equals battery volts, skip ahead to
test #7.4.
If the voltage does not equal battery volts, then
the F&R switch has failed.
Stop trouble shooting here and repair the problem.
When the repair is completed, completely retest the
vehicle before lowering the drive wheels to the
ground.
TEST 7.4:
Check the wires from the F&R switch to the logic card connector for continuity.
Stop, do not continue. Reaching this point indicates a failure in the Sevcon power unit or
an error was made during testing. Confirm all previous tests were performed correctly
before replacing the Sevcon power unit.
STOP
This troubleshooting guide is written in sequential order. All tests
must be performed in the order that they are written. Starting in the
middle or skipping sections when not instructed to do so may lead to
invalid test results.
Section 4
Electrical Troubleshooting
Page 21