Having problems with your 2003 Ford Explorer ?
Headlight and tail lights fade in and out when truck is running
\015 Alternator is fine and battery is ok but all my lights still dim in and out.\015
The diodes in the alternator are defective. No need to replace alternator, just the diodes. Remove alternator and if possible take alternator in to a alternator and starter rebuild shop. The alternator can be checked at a shop like this (these shops are rare and sometimes difficult to find) to locate the problem within the alternator. If this does not solve the problem, there could possibly be a bad ground connection somewhere....first make sure the battery terminals are clean and the positive and ground cables are in good condition.
Repair Help & Product Troubleshooting for 2003 Ford Explorer
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