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.
Control Box & Thermodetector
The thermodetector is a circuit in the control box which prevents the thermosensor from being influenced by ambient temperature. The control box receives various signals from; leading spark plug ignition coil (indicates engine RPM), the thermosensor (indicates engine temperature), and the vacuum switch (indicates engine load). After receiving a signal, the control box either allows the trailing spark plug to fire or prevents it from firing.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.
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