Alternator Overcharging 1989 5.0

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Hornet Driver

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There is a wire that sets the voltage drop to the alt and I don't have the wiring diagram. Anyone familiar with the shop manual troubleshooting and flow chart for this issue?

 

Seabronc

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Welcome to the Zone :D .

1. check the connection of the voltage sense line on the alternator, ( W/BK ), If this is broken or disconnected the alternator circuitry will not know what the voltage output is.

If that is good, try starting the engine, with all accessories turned off, remove the battery (-) cable . Then check the voltage at the battery side of the start relay, if the voltage is around 14V then the alternator is functioning properly. If that is OK, then check the following, in fact, do it any way.

2. check the grounding of the battery (-) cable to the engine block, (check the condition of the cable where the lugs attach, they may be corroded. Remove the connections at the battery and at the engine block, clean the lug and where it connects to the block and re-attach the cable. Also the ground strap from the back intake manifold on the driver side to the fire wall.

Good luck,

peace.gif


The charge circuit diagrams.

Charge power Dist Gas 001.jpg

Charge power Dist Gas 002.jpg

Charge power Dist Gas 003.jpg

Charge power Dist Gas 004.jpg

 
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