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 hybrid control module (HCM) monitors Ignition 1, Ignition 0 discrete wires from the ignition switch contacts and the Crank state message from powertrain control module (PCM). If HCM detects a mismatch between ignition switch signals and the Crank state message, it will set the DTC. The following table represents correct HCM power mode data:
| Ignition Switch Position | HCM and BCM inputs and Scan Tool Display | ||
|---|---|---|---|
| Ignition 0 | Ignition 1 | Crank State | |
| OFF | Off | Off | False |
| UNLOCK | On | Off | False |
| ACC | On | Off | False |
| ON | On | On | False |
| START | On | On | True |
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.