Sensor i hope?

I have a 2001 Nissan frontier SE the 6cylinder, no turbo, automatic transmission. My wife was not paying attention and thought the truck was running and so she put it in reverse and then realized that the truck as not running so she tried to start it while in reverse, when that didnt work she put it back into park and when she tried to start it, the cd player restarted and the wipers started and the guages peaked and whe truck made a fast ticking sound. i thought that it may have some how killed the battery but it does the same thing with the new battery in. i am stumped.

Starting an automatic in gear shouldn’t do anything because there are interlocks in place to make sure that doesn’t happen - unless those interlocks are not working, that is.

That fast clicking, where is it coming from? The area of the starter, by chance?
Not that I’m suggesting that the starter is bad: a starter shouldn’t fail because of you trying to start it in reverse. Maybe it just happened to fail as she tried to start it in reverse - coincidences do happen.
It could also be because it is drawing a lot of current because maybe something related to the transmission or torque converter is jammed. Not sure how that can happen by just putting a car in reverse, though…

When she tried to start the car in reverse, did it roll? Did it make any starting noises?

The reason all that stuff happened when she triued to restart it is cecause by turning the key she reenabled all the circuits. Ignore those things as possible symptoms. They’re normal.

Since she “thought the truck was running”, I’m going to assume that the truck had been running and died. It would therefore seem reasonable that if yuo determine why the truck stopped running, you’ll probably solve the no start problem too.

The “new battery”…is this fully charged? Did anyone check the cable connections when they installed it? Did anyone check the charging system? Perhaps the alternator has an open circuit.

The clicking is probably coming from insufficient voltage available to the starter motor. You could have a broken cable, a bad cable connection, even a bad key cylinder.

But it’s also possible that you’ve blown a fusible link. You have one that goes from the battery positive terminal to the underhood relay box. If it’s bubbled, it’s fried. You could jump it as a test, but be sure that of you need to replace it you do so with a proper link. It’s called a “fusibel link” because it’s a FUSE. It only LOOKS like a wire.

So you replaced the battery? Ok where you went wrong was not determining whether the starter was bad or had a bad wire or ground. There would be no real problem even actually starting the car with the AT in gear, but that is prevented by the interlock. So nothing likely was caused by this attempt to start the car. The starter is ticking because it is trying to engage the bendix gear. This is driven by a magnetic coil. If this coil does not pull the gear all the way back the starter will not turn. That is due to the contacts to turn the starter are at the far end of the coil body. A bad coil can cause this, also bad contacts or a bad motor. These are replaced as one piece. You can bypass the fusible link(if you have one) with a jumper cable from the positive battery terminal to the large wire on the starter. This will check the relay(if you have one) and the starter wire. Normally I just take the starter out and take it to the large parts chain for testing.