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.
Troubleshooting Of Electrical System
- Always refer to "CAUTION" of "General Description" in the same models service information before starting the diagnostics and repair.
- Always refer to the cautions of each article when diagnosing and repairing each system and component.
- The battery cable must be disconnected from the battery sensor ground terminal after the ignition switch is set to the OFF position, unless otherwise required by the diagnostics.
- When disconnecting a connector, do not pull the harness, but pull while holding the connector housing.
- Confirm the locking shape completely before disconnecting a connector. In addition, firmly push in the connector until a click sounds when connecting a connector.
- Be sure to prevent water or oil from contacting the connector terminals except for the integrated connector.
- When checking continuity between connector terminals, or measuring voltage across the terminal and ground, always touch tester probe(s) to terminals from the harness side.
When measuring the waterproof type connector terminal voltage, or the resistance between the terminals, use the check board.
If the probe is too thick to gain access to the terminal, do not push it in forcibly but use a mini test lead.
- When measuring the voltage or resistance of individual sensors or all electrical control modules, use a tapered pin with a diameter of 0.6 mm (0.024 in) or less and touch it to the tip of terminal. Never insert the tapered pin into the terminal at this time. Doing so may cause internal deformation and a malfunction can occur.CAUTION:
If a taper pin or the like has been inserted into the connector terminal, replace the connector.
- To check waterproof type connectors (which are not measurable from the harness side), touch tester probes on the terminal side and be very careful not to bend or damage the terminals.
- Securely fasten the harness with clamps and clips so that the harness does not interfere with the body end parts, edges, bolts or screws.
- When installing a harness and a component, be careful not to catch them on the harness.
- Sensors, relays, units, etc., are sensitive to strong impacts. Handle them with extra care so that they are not dropped or mishandled.
- When inspecting the airbag system, in order to avoid malfunction, always refer to "CAUTION" of "General Description" of the airbag system in the same model's service information. Ref. to AIRBAG SYSTEM>GENERAL DESCRIPTION>CAUTION .
Use the Manual With the Right Hardware
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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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