Hey, just yesterday I purchased an 09 TL. Delivery was at 6:30 and I was nearly home at 7:30. However, before I went home, I decided to stop by my local church for a minute. Then for a few circumstances, I had to wait in the car for a few minutes. So while waiting, I thought it would be time to setup my Bluetooth hands free link. During this, the car was on, but the ignition wasn't; in the ON (II) position. So I waited for a few minutes, approximately 7-10. Then I had done what I had needed and was time for us to leave.

So I try turning on the car, no reaction from the engine. It starts flashing in the dash when I try running the engine. Finally, I tried all sorts of things, and no good luck.

Then, someone passing by offered a boost and I said sure. So he got everything set up and began the process. But as much as he tried no luck.

HOWEVER, speaking to my friend later, he asked me a few questions. TURNS OUT, booster cables weren't connected properly!! And this messed up the ECU. I had to park the car at the church, by pushing it into a parking spot, and the dealer is coming to tow it to his shop today.

Is it really the ECU, how much is it gonna cost!?!

 

Turns out God won't save your ecu even if you are sitting in a church parking lot.

 

It's impossible to tell if it's the ECU just from what you said, but unfortunately, it is a possibility. It could be just a dead battery as well. Let the dealership advise you. You could always just swap in a battery and see if that allows the car to start and run before the dealer has it in their possession. Did you get the car with a warranty?

 

Your ECU is NOT Bad. You cannot hurt the ecu by connecting the battery cables wrong. What you have is a dead battery from leaving the ignition on without running the engine. It possible that you took out the main fuse to the car. Don't have my service manual so, Im not sure what fuse you should check.

 

^+1 for dead battery. Happened to my 09 same way after only 2 years.

 

^^ Actually, very good points- I'd go the new battery route (or charge your existing one) at least to try before bringing the car to the dealer- they might try to upsell you on a bunch of new components you likely won't need.

 

It is very likely that the battery is dead. My 2009 battery died just before warranty expired (4 years) so I got it was covered.

 

Does your state have a lemon law? in MA all used cars under a certain mileage carry a complete warranty for a few K miles.

 

So we went from a discharged battery to a Lemon Law consideration?

 

^^ LMAO!! I know....What is this world coming to?!

 

Fortunately for us, the engineers have put enough idiot-proof mechanisms to prevent the ECU from going bad. Most likely, if the booster cables where - to + and + to - then the main relay (PGM-FI) is burned or even before that the fuse that protects the main relay is burned. Doing a load test on the battery is also a good idea, since those 09's ones won't last more than 3-4 years.

 

Yup haha

 

My 2009 had a bad battery with a loose plate 2 years in. Would not take a jump so had it towed to the dealer, tehy replace the battery and all was good.

 

you have fuses for a reason.. if something were to go wrong, your fuse would have gone first before the ecu.