amp meter and battery light

[kona_mtb]

dash volt meter and battery light

My volt meter on my dash is very jumpy going from about 10 to 14 and my battery light comes on. The light isn't constant and fades in and out.

So I replaced my alternator and the battery light went away and the volt meter is less jumpy but still occassionally jumps. I only drove it for abou 5km could it need a sort of break in period or recharge period? I looked at the wiring which looked okay. Would the next thing be replacing the battery?

Any recommendations on what I could look at? I have relatively little experience with vehicle electrical issues so any help would be appreciated. Mudding season is starting here and need her running like a beauty

 

[joecrna]

Amp meter? Im thinking volt meter. If its jumping between 10 and 14 volts it could be a bad alternator. It could also be just a bad wiring connection, often on the ground side. You could get the alternator and battery checked for free at your friendly neighborhood Sears.

 

[kona_mtb]

Amp meter? Im thinking volt meter. If its jumping between 10 and 14 volts it could be a bad alternator. It could also be just a bad wiring connection, often on the ground side. You could get the alternator and battery checked for free at your friendly neighborhood Sears.

Ya sorry I got the two terms confused. How would I go about checking the wiring?

 

[joecrna]

Follow wiring from Alternator to battery. Check all connections. Check battery ground to frame and vehicle body. Follow + wire from battery to starter. Follow + wire from battery to fuse box under dash. At each connection, clean corrosion and tighten any loosness. It really is that easy. This still leaves a bad voltmeter gage and wiring running to it. In light of the meter and idiot light, I am leaning more to bad alternator or battery.

 

[kona_mtb]

so i decided to just go ahead and replace the alternator. this solved the battery light but my volt meter is still jumping. not as bad but still jumping. Could it be that the battery just needs to recharge. Or could something else be the problem?

 

[joecrna]

Either one, check your grounds. The negative cable on the battery and where the negative cable goes to the frame and the body strap. I assume the battery was tested when you replaced the alternator. Just a few deep/complete discharges can kill an automotive battery.

 

[92exp4x4]

Check your battery voltage with a meter. It should be in the neiberhood of 13.2-13.4 fully charged. With the truck running it should say about 14.2-14.5 on your meter. While cranking your battery voltage should not drop below 10.5 volts and it should rebound quickly when cranking stops. This is a good test of a battery's condition.

What is happening when the gauge jumps? Are there any loads coming on the system when it happens? Lights, heater motor, anything at all?

What amperage alternator did you get? Most Explorers had a 95 amp. The Limited had a 130 amp. You may want to upgrade for a little more juice.