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.
On-Board Diagnostics System: Function
The on-board diagnostics system detects and stores in the form of a code a fault that has occurred in any of the following input and output signal systems.
If a fault has been detected, the system tells the fault by causing the AT OIL TEMP warning light to operate as follows:
- Repeated flashing at 4 Hz frequency ... Errors such as battery trouble
- Repeated flashing at 2 Hz frequency ... No faults in the system
- Flashing at different intervals and frequencies ... Diagnostic trouble codes of corresponding faults
- Continued illumination of light ... Fault in inhibitor switch, idle switch, or wiring
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.