PSA: watch out when recharging keys

[Bdc101]

I have a Battery Tender Power Plus with 3 amp output. I was trying to recharge my keys and left it in the garage overnight with the key in "on" position but engine not running.



I woke up in the morning and the car lights up, but only barely. It won't start. My DMM says 11.4 volts.



I turned the car off and left the charger on it. Apparently the car takes more than 3 amps with the key on and the motor off. This is actually the big battery tender too -- the standard version is only 1.25A.



I'm using the terminals in the engine bay, if that matters.



Just your friendly PSA.