actually wondering about something similar....new to me car...should I unplug battery and let it learn me?

now to op.... stop freaakn out. u have a good vehicle and thousands of friends......ur good.

 

If you're that scared of doing it, you could get the dealership or BP to change it for you.

 

Not afraid, just wise enough to seek advice about things that I am not sure of so I can do the task correctly, ONCE.

I have spent more time under the hood than most and have learned it is much better to do things the right way...saves a lot of future rework and problems.

I appreciate your advice, but this is one job that I will do on my own.

 

I like that attitude. I wish I had the courage to work on my own car without fear of messing it up.

 

You will most likely lose you radio settings. Easy to reprogram. As for the computer and other electronics, nope. Do you lose all your memory from your desktop or laptop when you unplug it? You're just changing a battery, one in, one out...if you where leaving it out for a year, that might be a problem.

 

The cigarette lighter plug w/ a 9v battery type of memory saver will not work on a WK,you need a memory saver that plugs into the OBDII port.

If no memory saver is used you will loose the radio memory and all "learned" memory in the pCM so the engine and trans will act a little funny for a few days until it re-learns your driving habits.

 

FWIW, there is a TSB on the MyGig RER & REZ radios. Pull the radio fuse before disconnecting the negative battery lead. Stops the voltage spike to the MyGig unit when the lead is disconnected and precludes electronics failure. I remind them of this and put a copy on the front seat whenever I think the dealer will disconnect the battery for any reason. Had 2 MyGig failures and this could have been the cause.

Here: http://www.wkjeeps.com/tsb/tsb_wk_0800309.pdf This is for the 2008-2009 model years.

Also, what tjkj2002 said: The PCM long term and short term fuel adaptives will need to re-learn and the some of the radio pre-sets are lost. MDS was a little erratic and mpg's were down slightly for 1-2 days.

 

Radio/nav settings will be retained due to an internal battery in the radio. PCM/TCM settings will be lost and have to be relearned. No big deal.

 

Once my MY GIG went dead, I disconnected battery & reconnected. My Gig restated, had to reset presets but everything else was there.
However one time I had it in the dealership. they needed to disconnect battery and I was warned ahead of time that My Gig unit may not restart and they are not responsible.
They went and did it & I had no problems but they did give the warning so it must happen at times.

 

PCM gets reset, which can be desirable. Radio loses clock settings and current prefs but NOT loaded media data or playlists. Disconnecting the battery is the recommended precaution (here, at least) when messing with anything electrical.

 

Everytime I've unplugged my battery I lose the radio clock setting but not presets, and the MPG/trip gets reset.

 

I have an aftermarket radio installed and i lose my presets and clock. Other than that the only thing I lose is my MPG's on the EVIC which is no biggie.

 

On my 2010 I just recently changed mine out and it didn't even lose the stuff in the evic. I don't think anything was lost.

Is it really that big of a deal if you lose your radio stations?

 

Update

Thanks for all of the input.
I considered all options as well as the comments made by the service managers at 3 Jeep dealerships (???).

So, selecting the best of all, I got all of my tools ready.
I placed a 9v battery set-up into the 12v power outlet (cheap insurance if it does anything)
Loosened the hold-down.
Loosened the two terminal connectors and moved them aside to a safe place.
Removed a very heavy battery.
Placed the new battery in position and tightened the hold-down.
Connected the two terminals and tightened both connectors.
JOB DONE!!!!!

Next, checked:
Radio - all preset channels were there
Navagation - all presets were there
Drivers seat memory - # 1 & 2 were there

Haven't got to the trip odometer, yet.

So, all went well and my Jeep has a new battery.

Thanks again for all of your help.
Paul

 

I played my stereo out at the lake once and killed the battery. I boosted it to get it started, and the only things I noticed was the "hours" counter on the evic reset itself to zero, and I got an "transmission Overtemp" message too, however it went out after a minute or so and has never appeared again.