I have 1999 F250 with 97000 miles that has the alternator light come on during hard acceleration. I have verified that the voltage does drop below 12V. It starts OK, and the voltage is fine at idle.
Any thoughts other than replacing the alternator?
Also has anyone had the experience of a ringing cell phone causing the ECU to have random fault codes?
Why not try a belt first and make sure the tensioner is good.
Whitelightning
tighten the belt.
"Gary Ober" wrote: 1999 F250 97000 miles
The alternator light comes on during hard acceleration. I have verified that the voltage does drop below 12V. It starts OK, and the voltage is fine at idle. Any ideas besides replacing the alternator? ___________________________________________
The cause could be a loose belt or a bad brush/slip ring contact.
If the brushes are worn out, open the alternator and install a replacement brush kit. Clean the slip ring face with alcohol and fine emery cloth.
If the bad contact is due to contamination from oil or dirt, You may be able to clean the slip ring without disassembly by shoving an alcohol-soaked rag through the vents while turning it by hand. Follow with emery or a pencil eraser.
Good luck.
Rodan.
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