92 Dodge Caravan is completely dead but the battery has a full charge. My son installed a new radio without any amps. Seemed to work fine for a week or so but now the car has no power, wont start, nothing come on in the inside. All fuses appear good.

Seems you have a dead battery. Could be anything related to the charging system (alternator, control, wiring) or the battery itself. It takes a methodic process of testing to determine the cause(s).

Start by having battery tested and charged. If the battery checks ok and holds a charge then "likely" the problem is with the charging system, but it's a multistep process of elimination and very few parts store do a complete full load battery test.

If the battery test fails then you'll need to replace the battery and then promptly have the charging system tested to verify its working or you'll have another dead battery.

Once the battery and charging system has been verified functional you need to have a parasitic current test done. Excessive parasitic draw can ruin a new battery in a few months depending on your driving habits. Is this a daily driver or every other week or longer?

How much is this going to cost? ????? Without testing to find out what the problem is , no idea . Your best bet , take it to a qualified repair shop an have it diagnosed .

It could be a couple things. Take it to a shop or a place like auto zone and have them test the alternator and the battery, its free :) If they both are testing as good, the next thing would be to check the battery terminals and connections. It simply is not getting the enough charge back to the battery for one reason or another.

Either its a bad new battery or tour altenator isn't charging it. Jumpstart it.

Is the battery old & possibly dead ?

Have you checked to see if all of the fuses are good? That could be the cause for the radio and the tripometer not working.

I put a new battery in the key fob for a 2008 Dodge Grand Caravan, and, at first, it still didn't work. Took it to the Dodge Dealer, who said the fob was dead. NOT SO! My husband put a little piece of cardboard on top of the battery so the battery contact was improved, and the fob works fine now.

THER ARETWO COPPER CONACTS IN THE STARTER SOLENOID THAT ARE REPACABLE.IF YOU TAKE THE COVER OFF THE SOLENOID PART OF THE STARTER AND PULL OUT THE PLUNGER I THINK YOU WILL SEE THAT ONE OF THE CONTACTS IS BURNT SHORTER THAN THE OTHER CAUSING YOU TO JUST HEAR A CLICK WHEN YOU TURN THE KET TO START.ANY STARTER REPAIR SHOP SHOULD STOCK THESE PARTS FOR BETWEEN $10 & $20 .

Why do you feel it isn't charging. Are you going off of a voltage ereadiing? I ask because if it is reading 12 v at the battery , Do not run it very long. The lower the voltage the higher the amps. An Alternator will ocweheat and self destruct if it is working at its high limit for 15 minutes or so. A heavy charge iis normal for 30 seconds or so to make up for the starting drain. But, should show a gradual rise within seconds. An alternator is for battery charge maintenance only and should never be used to charge a dead battery. A dead battery can an will over tax the alternator for too long. A defective battery will do the same thing and it is usually why you have to change the alternator in the first place. So, If your battery is dead or extremely lpw, it should be charged with a charger Do not put a new or rebuilt Aly. sgainst a possible bad battery. It costs nothing to have your batt load tested by a auto parts store. Good Luck=Ned-.

Then your problem is either due to; Bad Voltage Regulator, or Bad Altenator.