Hi fella's

Hey, finally my first post. I've done a lot of reading but hey here we go....

I'm chasing some advice on a problem with the wife's TJ AWD.

Last Wednesday she had the 180K service done at Mitsubishi. Amongst other things they said they checked was the battery electrolyte & fluid levels and they replaced the air con and the power steering belts.

The very next day & 3 starts after leaving the dealership the battery is dead flat (10.3 volts - dropped cell). Got a new battery, re-learned the ECU d4 & 3.5 mode button and all looked good. However today on the way home my wife turned the air con on and the call stalled - everything dead. Switch off air con and all is good?

The old battery had never given any hints on starting, no charging lights etc and air con has worked fine all summer. New battery is now at 13.97 volts and is charging fine.

Any idea's would be greatly appreciated.

I'd say the battery dying was just coincidental - that seems to be the way they go nowdays, drop a cell and die.
Re the engine stalling when the aircon was switched on, I'd say that was due to the re-learning procedure and the idle not being compensated for....give it a few days and see how it goes.
So, I reckon no problems.

lols my battery was slowly going dead, all i did was start the car, disconnect the battery and quickly swap over the new one.

Re the engine stalling when the aircon was switched on, I'd say that was due to the re-learning procedure and the idle not being compensated for....give it a few days and see how it goes.
+1 to this. I've had my TJ stall when the auto has been re-learning itself, but it's only been in the initial period after reset. Give it a few days.

lols my battery was slowly going dead, all i did was start the car, disconnect the battery and quickly swap over the new one.

You changed the battery with the car running?
Can you even do that without blowing fuses?

You changed the battery with the car running?
Can you even do that without blowing fuses?

You can but is a great way to surge the power through the car and blow all your diodes in the alternator as well.....

I read somewhere that the regulator takes battery voltage as a reference and if it suddenly is disconnected the output voltage can jump to 25 volts, even at idle. Don't know how true that is. I imagine that the diodes in the regulator/alternator would die before the ECU/BEM get fried. Hopefully. lol

Thanks guys