Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit Description
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).
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.