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.
Auxiliary Battery: Inspection
- Check that the battery cables are connected to the correct terminals.
- Disconnect the battery cables when the battery is given a quick charge.
- Do not perform tests with a high voltage insulation resistance tester.
- Never disconnect the battery while the engine is running.
- CHECK BATTERY ELECTROLYTE LEVEL
Check the electrolyte quantity of each cell.
If under the lower level, replace the battery (or add distilled water if possible). Check the charging system.
- CHECK BATTERY VOLTAGE
- After having driven the vehicle and in the case that 20 minutes have not passed after having stopped the engine, turn the ignition switch ON and turn on the electrical system (headlight, blower motor, rear defogger etc.) for 60 seconds to remove the surface charge.
- Turn the ignition switch OFF and turn off the electrical systems.
- Measure the battery voltage between the negative (-) and positive (+) terminals of the battery.
Standard voltage: 12.5 - 12.9 V at 20°C (68°F)
If the voltage is less than specification, charge the battery.
- CHECK BATTERY TERMINALS, FUSIBLE LINK AND FUSES
- Check that the battery terminals are not loose or corroded.
If the terminals are corroded, clean the terminals.
- Check the fusible link, H-fuses, M-fuse and fuses for continuity.
- Check that the battery terminals are not loose or corroded.
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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