Transmission acting up what do you think
 

My sisters cooper started acting up ??one day the lights start flashing & it doesn't shift right. I call the dealer & they said it sounds like the battery needs changed(it was still the original from 2002) So I replace the battery & test the alternator which was bad. So it has a brand new battery & Alternator but I can't figure out how to reset the transmission. The dealer says $390 to get the trans flushed & reset which they say may fix it.

Has anyone had this happen or have any comments Thanks in advance

I'd guess it might just need the tranny "flashed" meaning the TCM reprogrammed

Automatic transmission programming
 

My buddy Andy Terani owns "Empower Inc." in Burbank at Hollywood Way. He reprogrammed my VCT auto. transmission a few days ago and its running great! The programming must be done on a completely cold engine. It may take a couple tries to get it right, but so far so good. I have a 2006 Mini cooper. My battery went dead which caused the transmission to act up. The battery must be the correct CCA. I was quoted $7,000 for a new transmission from the Mini dealer. Mind as well try the programming first to save money!!

Hello, I have fixed several mini cvt trans problems. I will try to help, I am a mini tech at the dealer "master certified" I would start with having the cvt adaptations re-set, the service advisor may not know what that means but a tech would. This procedure may also be known as "flashing the transmission control module" after this is done make sure the mini dealer also delete's all faults. Next drive the car for a few days and if the trans is acting normally then you are in luck. If the check engine light or mil light shows back up and the trans starts acting up, then the car needs to go back to get the faults checked. If faults are stored in the trans control unit then the control unit may be bad, the tech will then need to replace the control unit and if indeed the control unit was bad then your problems are resolved. (If there are no faults then the transmission is the problem, the main belt internally is worn out.) If the problems come back after the control unit is replaced, then 90% you need a new cvt transmission if the same faults are stored. The reason I say 90%, there is a possibility there could be an issue with the wiring harness for the trans, or a problem in a connector (water, rodents, etc.) The tech should be testing wires and connectors before replacing anything. This is not an easy process, as you can see it is a step by step process to propperly diagnose the problem. If you have any questions, just ask. I have a shop in Aliso Viejo that I am in the process of opening, it is for I specialize in Mini Coopers. Thanks, Ryan.

Hi Ryan,

Where is your shop located at? I believe my mini may need the main belt replaced on the CVT.

did it start working normally immediately or did it take a day or 2 once u replaced the battery

you can reset transmission control module easily after reading this. Read Here