Troubleshooting
Experiencing power problems? Follow these steps to help diagnose the underlying issue. Most power issues our customers experience stem from a problem with their battery or batteries.
1. Check your battery or batteries. With the engine and ignition off, check the voltage across the front battery red and black terminals with a volt meter. The reading should be at least 12.3. volts DC.
If there are dual batteries, disconnect the positive of the front battery, then measure front and rear batteries voltage with a VOM, one at a time. If the voltage is below 12.3 volts DC, then you need to replace. If there are dual batteries, replace both even if only one batter is below 12.3 volts DC.
Important note: Do not charge the battery with a charger before checking it. Check the battery as-is.
2. Ensure proper connection. Make sure there is a heavy gauge wire (about 3/8" thick) running from the red post on the alternator to the red post on the battery.
3. Ensure proper ground. Make sure there is a heavy gauge ground wire (again, about 3/8" thick) running from the alternator mount to the negative side of the front battery or to the vehicle chassis if the battery is also solidly grounded to the chassis.
Important tips for ensuring a proper ground:
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Do not ground the alternator to the engine. This is not sufficient.
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Ensure there is no paint on the alternator mounting bracket. Thick paint on the mounting bracket can cause an insufficient connection to ground the alternator.
4. Align belts. Proper belt alignment is critical for alternator function.
First, verify that the belt that runs the compressor and alternator is seated on the correct grooves. The compressor will usually have eight grooves, and the alternator will have six grooves. Next, align the belts correctly using a belt alignment laser, or use the operations manual to do it yourself. Typically (but not always) the belt should ride on the rear-most six grooves of the eight-groove pulley.
5. Use the alternator checklist. Download the Alternator Troubleshooting Checklist and run all the tests as described. This checklist is designed to correct most alternator problems.
If you follow these steps and continue to experience problems, please contact us so that we may assist you.
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