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Hello All
Picked up my 94 9000 stored for the winter.Put the battery in and it fired right up.Was enjoying the ride home when I noticed the voltmeter on the dash starting to drop to 7.By the time I got home I had no dash lights, tach or speedometer,fuel gauge.The next day,the engine would turn over but would not start and no dash lights.Not sure where to start an
Thank you
PS I did charge the battery,but no change
 

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Have the battery load tested. Sounds like it has bad cells and is showing 12v as surface voltage. If the battery froze at any point then it is toast.
 

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Have the battery load tested. Sounds like it has bad cells and is showing 12v as surface voltage. If the battery froze at any point then it is toast.
Unlikely scenario you just stated, the owner mentioned the same day his issued occurred tha battery was new. More likely a few situations occurred, make sure the belt is tight on the alternator and slipping, recharge the battery to a full charge, start the engine and with a voltmeter measure the voltage between the positive and negative pits of the battery, at idle the reading should be at least 13.6 volts. That means the alternator is charging, also with same voltmeter put the dial to measure AC volts, there should maximum voltage of 300 milivolts or 0.3 volts AC. The alternator requires a 12 volt feed via a wire to the alternator, this wire is on the connector with maybe 2 or more wires on it as well. A second wire on the alternator on that connector , connects on the alternator side and the other end of that wire connects to the positive post on the battery, this wire is monitoring the voltage output of the alternator being applied to the battery, in other words if the voltage is less than approximately 13.2 it controls the alternator to put out more amperage. The third wire is a wire connected to the battery indicator on the instrument gauge cluster - if the output of the alternator drops below approximately 12. 2 volts it turns on the red battery indicator on your dash informing you there is a problem ( this indicator should have come on while you were driving because you said the voltage gauge dropped to about 7 volts D.C. ) There may be a fourth wire on the alternator connector, might be ground wire for the alternator circuit. The big fat wire at the back of the alternator is the high amperage 20 to 60 amps depending on the design to charge the battery and help provide power to your electrical components, radio, lights, wind shield wipers,etc. This Fat wire also provides the voltage output of the alternator and as mentioned should be appropriately 13.2 to 14.8 volts D.C. In order to test an automotive electrical charging system your battery has to be fully charged !!!!! If when you measure the voltage of the fat wire output to the battery and compare it with the battery voltage it should not differ mor than 0.1 V D.C..

Good luck.
 

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I had a 9000 of a different year (can’t recall what year). If memory serves, there was an issue with that high amp wire shorting and burning out. I also seem to recall it was cheap to replace the brushes on the alternator. Yours may be different, though.
 

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First thing to check is the fuse panel and the voltage at the circuits there. Then the voltage from the alternator.
 
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