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.
Charging System Resistance Check
This tests will indicate the amount of voltage drop across the generator output wire, from the generator output (B+) terminal to the battery positive post. They will also show the amount of voltage drop from the ground (-) terminal on the generator to the negative battery post.
- Engage the parking brake, make sure the transaxle is in PARK (A/T) or NEUTRAL (M/T) and start the engine.
- Set blower control to the maximum position.
- Turn on headlights and set in high-beam position and turn the vehicle interior lamps on.
- Bring the engine speed up to 2400 RPM and hold.
- Touch the DVOM (Digital Voltage and Ohm Meter) negative lead directly to the positive battery post.
- Touch the DVOM positive lead to the B+ output terminal stud on the generator (not the terminal mounting nut). The output voltage should be no higher than 0.6V. If the voltage is higher than 0.6V, touch the DVOM positive lead to the terminal mounting stud nut and then to the wiring connector. If the voltage is now below 0.6V, look for dirty, loose or poor connection.
- Touch the DVOM negative lead directly to the negative battery post.
- Touch the DVOM positive lead to the ground terminal stud on the generator case (not the terminal mounting nut). The voltage should be no higher than 0.3V. If the voltage is higher than 0.3V touch the DVOM positive lead to the terminal mounting stud nut and then to the wiring connector. If the voltage is now below 0.3V, look for dirty, loose or poor connection.
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:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
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