Sevcon Controller Diagnostic Codes
1. A Light Emitting Diode (LED) is used to indicate controller status.
2. When operating normally, the LED will be ON continuously.
3. If the controller is faulty, the LED will be OFF.
4. If there is a vehicle fault the LED will flash.
5. The information given by the flashing is as follows (below):
The Sevcon controller is identified by its blue case
Low resistance or short circuit between M1 and B- producing a low voltage across the Mosfets.
Mosfet s/c, motor s/c to B-, power wiring.
Contactor coil short circuit.
Coil s/c, coil wiring.
Contactor welded or wiring fault giving a high voltage between M1 and B- before closing the
Welded contactor tips, power wiring.
No high voltage (approximately equal to battery voltage) between M1 and B- after closing the contactor.
Coil wiring, power wiring, motor o/c.
Accelerator input high at start up.
Accelerator wiring. Accelerator set towards maximum.
Incorrect battery voltage – less than 13V or higher than 45V.
Correct battery voltage, loose connections, discharged battery.
Controller has overheated. Allow controller to cool.