Taylor-Dunn MB-238-00, Operation, T Roubleshooting And Replacement Parts Manual

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Electrical Troubleshooting
Troubleshooting Page 16
STOP
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.
After any repairs are made, completely retest the vehicle before
lowering the drive wheels to the ground. Failure to retest the vehicle
could result in unexpected movement of the vehicle resulting in injury
or property damage.
B+ Terminal on the Sevcon controller
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.
Shorted Solenoid Coil: Disconnect the logic card connector and measure the
resistance across the solenoid coil. Depending on the solenoid or contactor you
vehicle is equipped with, the resistance should be 25 ohms or higher (nominal). A
reading less than 25 ohms may indicate a shorted coil.
The control logic may have failed.