My troubles didn’t end when I hooked up the battery charger. I put one of the new code cut RFID keys in the lock cylinder. The immobilizer light (yellow arrow) did not come on and stay on when the key was inserted in the lock cylinder and turned to the on position, as it should when registering the first key. Instead it just blinked, which is what it does when there is no RFID signal or the wrong RFID signal. I didn’t know whether there it was a misprint in the manual or whether I had toasted the new ECU by letting the battery go dead. Not wanting to buy a new ECU, I tried again. And again. And again. Then again with the other code cut key. If you count the 1/2 hour for each attempt, you’ll notice that the car has been tying up a bay for at least 2 1/2 hours on a 1 hour job, not even counting the time it took me to replace the control unit.