Ballast Wire Check
- On most models, such as the TR7, a pink/white ballast resistance wire is built into the wiring harness leading to the ignition coil. The wire causes a voltage drop so the 12-volt supply may be used to power the 6-volt ignition coil. During engine start, the resistor is bypassed to apply 12 volts reduced by starter load directly to the coil.
- To check resistor wire, turn ignition switch "OFF" and attach ohmmeter leads to each end of pink/white wire. Resistance should be 1.3-1.5 ohms. If not, replace ballast resistor wire.