[fliptuner]

My neighbor asked for help cause his '11 Sienna wouldn't start. I went over with a booster pack to find that he'd jumped the van to another car battery (on the ground) backwards.

After I disconnected the jumpers and looked over the main fuses (not blown), I got him to crank, just to see if it would do anything (if nothing happened, I'd assume something was blown). Lo and behold, the starter solenoid rapid-clicked, just like a normal drained battery. I hooked up my booster pack and it fired right away.

My questions are: Should I look anything over since it was hooked up backwards? Does this model have some kind of reverse polarity failsafe?

It was straight batt to batt, hooked up for at least 3-5mins. Booster batt had 12.6V. Once started, alt was charging at 14.2V and the van seemed to run OK.