DIESEL HARD START/GLOW PLUG FAILURE-BAD G/P CONTROLLER

Model and Year 1982-84 "C/K/G/P" - 10-30 WITH 6.2L DIESEL ENGINE

The glow plug controller has three (3) internal circuits: a pre-glow timer, an after-glow timer, and a circuit breaker. A failure of the pre-glow timer will cause the circuit breaker to operate. The fact that the circuit breaker is controlling the glow plugs can be determined on a cold start by observing the glow plug light on the instrument panel. If the pre-glow timer is working, the glow plug light will continue to cycle on and off with the ignition key on and the engine off. If the pre-glow timer is not working, the glow plug light will only cycle once with the ignition key on and the engine off.

If it is found that the circuit breaker is controlling the glow plugs, the glow plug controller should be replaced. Extended operation of the glow plugs with the circuit breaker can cause premature failure of the glow plugs.

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