Voltage problem

[jjlbur]

96-F250 PS Diesel, Check alt and batteries, all good . still battery light comes on at running speed , low rpm goes off, high rpm goes off mid rpm comes on, what next to check?

 

[94f450sd]

check the connections on the alternator.i had an issue with the big plug and the single wire plug on both of my trucks.

 

[Dieselpwrdredneck]

Did ya check the voltage coming off the alternator with someone holding the truck at high rpm's?

 

[jjlbur]

What did you do to fix?

 

[94f450sd]

i replaced the connectors

 

[Brad B]

I've had the same problem. Did you just splice new connectors on or did you replace the whole wire ? Did you get the parts from a dealer or parts store?

 

[jjlbur]

Changed the connection no change, still same problem

 

[JOAT]

Pull the alternator and take it in to be tested. Being RPM related is usually a bad alternator. Most parts s have test stands, Autozone for sure

 

[jjlbur]

Already bench tested good

 

[bushpilot]

could the BELT be slipping ??? i mean since the indicator light is OFF @ idle
and comes on (showing no charging) at speed !?!