Circuit Description
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The WAIT TO START light is illuminated by PCM when glow plugs are commanded on. When PCM is commanding WAIT TO START light on, voltage potential of circuit will be low (near zero volts). When PCM is commanding WAIT TO START light off, voltage potential of circuit will be high (near battery voltage). Primary function of PCM is to supply ground to the WAIT TO START light control circuit.
DTC will set when the following conditions are present:
- WAIT TO START light is requested on.
- Voltage to WAIT TO START light control circuit is high (near battery voltage).
Or
- WAIT TO START light is requested off.
- Voltage to WAIT TO START light control circuit is low (near zero volts).