Symptom
Control does not operate (line contactor drops out).

Possible Causes and Test Procedures
* Short circuit in armature (terminal A1 to A2).
Disconnect power cables from traction motor terminals
A1 and A2. Check for a short circuit between
the terminals.

* Short circuit of armature terminal A1 or A2 to battery
positive or battery negative.
Disconnect power cables from traction motor terminals
A1 and A2. Check for a short circuit between
each terminal to battery positive and then each terminal
to battery negative.

* Short circuit between power cables to the armature terminals (A1 and A2).
Disconnect power cables from traction motor terminals
A1 and A2. Check for a short circuit between
the power cables.