buddy hooked battery up backwards.

[CheapThrills]

So a buddy of mine hooked his battery up backwards, fried the alternator, and now when we went to put my alternator in to see if it works, it doesn't. I read somewhere there is a 175amp fuse somewhere in between the alternator and battery.. anyone have a clue?

-it's a 2000 ranger 4.0 4x4 5-speed

 

[exbass94]

The wire between the battery and alternator might be a fusible link. There's a good chance the computer is fried too.

 

[88_Eddie]

There's a good chance the computer is fried too.

that's what i was gonna say. we had some idiot do the same thing to his jaguar when i worked at autozone. he just went and grabbed a battery off the shelf, paid for it and installed. he blamed autozone for it and we ended up having to pay to have his car fixed b/c he was a dumbass.

 

[shane96ranger]

I don't believe there is a fuse in the alternator to battery cable. You didn't say..... does it run?

EDIT: The fuse theory is easy enough to prove. You can run a temporary wire between the battery and alternator.

 

[Capt Jay]

First off..........get a new friend that can tell the difference between "+" and "-" and red/black. Second check fuses and wires. If they are bubbled (wires) they may not look bad on the outside but the actual wire is severed including the battery cables.

 

[koda6966]

I hate stupid people.

 

[CheapThrills]

the truck does run, but the battery gauge doesnt move, and his gas gauge is stuck on e. pretty sure he fried the resistors in the instrument cluster..

 

[gimp44rsr]

punch your friend in the face!!!

I would start by checking your wires and fuses but when you check the fuses use an ohm meter. The reason is that a fuse can blow and it can still look good to the naked eye. After you check the wires and fuses you could take voltage reedings. Check the battery voltage first and you should have close to battery voltage at the points you are checking. I hope that helps a little I had another new tech do that to a customers car he fried the computer on a $100k car shit sucked.

 

[Jody]

Check the main fuses (largest ones) and relays that are in the engine compartment fuse box.

 

[CheapThrills]

thanks both, i'll let him know that.

 

[Duane867]

There is a 125 amp mega fuse in the battery junction box. Its there to help stop severe damage in case s like this. Check there 1st as I am reasonably sure that is the problem with charging. ( could have fried the voltage regulator on the alternator but I dont know..) There should be a little window in it so you can see the circuit inside it. If not you can either remove the fuse and ohm it out ( should read around 1/10th of an ohm if good. ) OR simply put a small current through it and check for continuity.
Now as to weather or not any thing else was fried ? More then likely. Your lucky the PCM didn't get frucked up real good. Check the central junction box as well.