The engine cranked normally but lost controller and injector supply under load through a heat-sensitive relay contact.
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
- Cranking voltage
- Controller communication
- Relay input and output voltage under load
- Temperature at failure
A disciplined path
- Confirm the missing combustion command
- Back-probe relay supply and output
- Apply controlled heat only as permitted
- Replace the failed relay and verify hot restarts
Decision point
The voltage drop across the closed contact identified the relay; resistance measured cold had appeared normal.
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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