I recently inherited a 2007 Crossfire and tried to replace the stereo because the stock one wouldn't change station or volume or anything. I swapped out the stereo with no real problems, but the car won't start with the new stereo in. When I put the key in the ignition, the car has power and there's no issues. But when I turn the key, the power immediately cuts off and stays off. If a disconnect and reconnect the battery the power works normally again.

If I plug the stock radio back in, the car will start like it's supposed to. I have the Infinity Modulus stereo with two antennas, one for AM/FM and one for GPS. I vaguely remember my dad saying something about a security feature in the radio at one point, but that was many years ago and nobody else remembers so maybe I'm wrong about that.

I just tried it a few more times all with the stock radio plugged in. I turned the key and the power immediately cut off. Then I waited a few minutes and the power came back on. I turned the key and the power cut again. Then I disconnected and reconnected the battery. After doing that the car started like normal on the third attempt. Also at some point during this I realized the stock radio was now working correctly.

Does anyone know what the issue is? Do I have to do something special to change out this stereo?

 

I would keep the stock stereo in until I was sure the car was dependably starting every time.
Then and only then would I try the stereo exchange.
Swapping wires is required on some radios, most match color for color, but some wires have different coloured wires connected to each other. On the Kenwoods I have seen two wires are switched to the same two coloured wires on the other stereo.
The stock radio in North America at least, needs no recoding.

 

The radio is not at fault here, get that idea out of your head.

This all reads like a battery that has a fractured connection between a battery post and internal plate or bad battery cable clamps or something similar. I sure could be wrong, but I've had this happen before - and I found it by turning the headlights on with the engine not running - and using pliers to wiggle the battery terminals/posts, when I put stress on the one post, the lights cut in and out, which indicated a bad connection inside the battery.

A new battery fixed that.

 

Exactly!

 

This was the problem. After shifting and retightening the battery connectors, the car started on the first try with both stereos. What a relief!

 

Thanks for the update. So many people ask for help and never respond with the solution. This helps everyone to understand the outcome.

 

It also helps everyone understand how right I was.