I'm new to this forum and just bought a 99 jeep Cherokee sport with 92000 miles. The lights dim when heater is on and the battery gauge drops then licks back up. Also just today I hear a light squeeling sound when I give it gas. No check engine lights or nothing and the jeep looks to be in great condition under the hood. What should I do, hopefully I can save a buck and not have to bring it in to the mechanic. Any help would be great. BTW I have upgraded the exhaust system with a cold air intake and flowmaster exhaust also new stereo installed but that's it so far. Thanks!

 

Get a multi meter and test your battery and alternator. There are plenty of write ups all over the web on how to do it

 

Sounds like a worn out serpentine belt.

 

go to autozone, napa, or orileys and have them do a load test on the batt. , alt and check the belt and idler pully. Hell its free

 

could be blower motor too,mine was seizing up drawing so many amps it burnt up my switch then froze up

 

start the engine, turn on high beams, wiper and blower motor and see what battery voltage you have at the battery with a multi meter. let us know

 

So I changed the belt because it was glazed and had some cracking. Then tested voltage of battery and alternator and they crank up with all accessories on and blower on to 14 volts steady even at 2000 rpm. Maybe I will buy a battery at napa cause mine is 2 years old. Possibly the police officer that owned it before me killed the battery. I'm going to keep an eye on it and maybe put a new 800 cca napa battery in. Hopefully everything else goes smooth cause I love my new Jeep. I think it does need a new valve cover gasket case I noticed a small leak on the engine block back left corner.

 

So belts good and alternator is good. I'd have the battery tested. Go to auto zone or orileys. They'll test it for free.

All jeeps leak it's just how much are you willing to put up with.

 

Had basically the same problem. Make sure your ground is good. My alternator was already changed ended up replacing the battery when my 2nd starter went bad so that wasn't it. So what I ended up doing was changing the whole negative wire and the whole positive wire to the starter and the junction box which is where the alternator wire meets up too... You might be able to get away just doing the negative or cleaning up all your terminals. If you do decide to change the wires, use the marine post and get the wires that slide onto the marine post at one end. It's alot better then the pre-fab ones. There are a lot of write-ups on replacing your wires as well on the forum.
Good luck,
Lee

 

I've had the exact same problem. Finally my alternator quit yesterday. Changing it tomorrow.