A hot restart failed only after a short soak, and the crank signal returned before the vehicle reached the shop.
Why this matters
The value of this case is the order of evidence and the verification step. The same symptom on another vehicle may have a different cause.
Evidence to capture first
- Hot-soak time
- Cranking rpm PID
- Oscilloscope pattern at the sensor and controller
- Power, ground, and temperature
A disciplined path
- Build a safe repeatable hot-soak routine
- Capture scan and scope signals together
- Compare sensor output with controller input
- Verify the repair through several heat cycles
Decision point
Time alignment showed the signal failing before rpm disappeared, supporting a circuit-level repair.
Source desk
Use current model-specific service information for specifications, connector locations, disabling procedures, and tightening values. The following public resources support the broader safety or system context used in this guide.
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