Hi all,

I recently bought an Optima yellow top battery and everything was going well since I installed it less than a month ago until last night. Please take note, while I was in class...everything was off in the XJ, no cell phone chargers were left hooked up or anything.

So while replacing the battery I had to replace the terminal connectors as well. Like mentioned already, everything after that went well up until last night. For some reason when I pulled it into the driveway to jump out to open the garage...the XJ died. Not sure what happened, but prior to pulling into the neighborhood my stereo(stock) died. Me not thinking anything of it, but just a blown fuse or something. After the stereo died, I noticed the interior lights and headlights were getting dimmer and dimmer.

Well I still had the old Napa battery sitting in the garage, so I thought that considering how late it was I'll just swap them and see if the old one still has a decent charge to get me back started. Everything cranked up fine and worked well.

Anyone know what the issue could be?

Note* I was unable to get the charge of the Optima battery because my gauge has that intermittent connection that will say either, "check gauges", or "airbag"...that will cause primarily the battery gauge to cut out.

Hope you all can help! Thanks in advance.

V/r,
-awsgrayrd

 

so when you put the old battery back in all the lights and sterio worked?

 

Yeah, everything worked fine!

V/r,
-awsgrayrd.

 

something is wrong with your alternator. The alternator wasn't running the car so you were driving on juice from the battery, once the battery was under 11.5 volts or so it can't power the engine and electronics so the jeep shut off.

Pull your alternator and go get it tested you'll see that there is an issue.

 

x2 altinator. No GEN light? You can pull your negative cable while the jeep is running and if the alt is bad then the jeep will stop running.

 

Alternator is bad, or ecu is shot. the alternator doesn't have a voltage regulator, it is built into the ecu and if it fails the ecu will neEd replaced. It's not likely to be the ecu, but a slight possibility.

 

Thanks for the quick reply!

Yeah, I kind of thought that it was possibly the alternator...but it just seemed weird that after the swap to the old battery everything cranked right up.

So how much am I looking at here and where can I get the alternator tested?

V/r,
awsgrayrd.

 

Your old battery probably wasn't the problem afterall. Its your alt. Had the exact thing happen with a buddy one time. First the radio then other elecs. Stopped at a store and guess what...we had to call someone to come get us.

 

Hmm, well so much for driving it to class and then the base to workout!

Has anyone here ever replaced the ECU?

Or can supply me a write up that's been done on it?

Well looks like I have a project this weekend. If anyone knows what pricing/model numbers/brands to go with that would be great! I'll would like to order them so I can get them by this weekend.

Thanks all!

V/r,
awsgrayrd.

 

Also, that Optima is going to be deeply discharged. Make sure you recharge it correctly by the Optima website or you'll have a really nice yellow top door stop.

The ECU is on the drivers fender beside the air box. Three bolts hold it on and theres a plug that has to be unbolted. I SERIOUSLY doubt that's the problem.

You can test the alternator yourself. Put which ever battery in the Jeep that has a charge on it. Start the engine, use a volt meter to check the voltage at the battery. If the voltage is less than 13v then you need a new alternator.

 

From my understanding the Yellow Top Optima battery is a deep cycle battery. The Red Top battery is for automotive use. A deep cycle battery is not meant to be constantly recharged by an alternator.

 

I've heard Optima's quality is going down the drain in the past year or so on a few other forums.

I had a similar situation happen to me but it was after a wheeling trip, even had a yellow top too. My alternator ended up being caked up with mud because of it's stupid location at the bottom of the motor..

 

I'll try and do this tonight after class.
This is correct, but I bought it due to wanting a battery that will last a bit longer in life due to Colorado's winter months and because I'm redoing the whole stereo.
Never heard the rumor about the quality going down, so this is a first.

Well the last few days I have been driving in snow and slush, but doubt that's too much of a problem, right. Considering its snow, slush, and mag chloride.

V/r,
awsgrayrd.

 

I've run yellow tops in several on my cars/trucks for years with no problems, I've used an abused them

 

Optima had a rough patch of quality which seems to be behind them from what I've been reading (no personal experience). In this case, the battery certainly doesn't seem to be at fault, this screams (as others have said) to be a dead or failing alternator. Relatively cheap and easy to replace fortunately.