2002 Dodge Ram gauge problem

2002 DODGE RAM
26,000 MILES • V8 • 2WD • AUTOMATIC
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MATT2727
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  • 3 POSTS
i have a dodge truck that keeps on having the same problem, when i start my truck the battery voltage gauge stays in the middle but as soon as u start drivin the gauge moves up and down going frum the middle to high and it jumps around slowly like that, do u know what the proble would be?
Feb 27, 2010 at 12:56 PM
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CARADIODOC
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Start by measuring system voltage while the problem is occurring. The power outlet is a convenient place to measure. If the voltage stays steady while the gauge goes up and down, suspect a problem in the instrument cluster computer. If the voltage follows the gauge, the voltages will give a clue.

Charging system voltage must be between 13.75 and 14.75 volts. If it goes higher than 15 volts, suspect a problem with the voltage sensing wire at the engine computer. If it goes down to around 12.0 volts, you'll need to measure the voltages on the two small terminals on the back of the alternator. One will have full battery voltage. The other one will have less but it should never have 0 volts. That's the terminal that will provide important information.

caradiodoc
Feb 27, 2010 at 1:10 PM
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