[Mr V]

I fear that things may be getting confused with discussions of relating the current a motor will draw vs its resistance and the need to determine the wattage of a solenoid.

If the item in question is indeed a motor and is used in car doors then it is legal with no restrictions. The power draw of the motor is only relevant when choosing the wiring and thus breaker sizing, to prevent nuisance trips.

Solenoids on the other hand are limited in their power rating. Calculating the wattage from the resistance is valid. A solenoid acts as an inductor. It will generate back EMF as a function of the rate of change of current flow. If an inductor is fed DC current an equilibrium will be reached where there is no change in the current flow and the current flowing through the coil will be dictated purely by the resistance of the wire that makes up the coil. Yes the fact that part of the core is mobile will induce some back EMF as it moves but that too will stop as the core comes to a stop at the end of travel.

So because of the way an inductor works the peak current of a solenoid is determined by resistance and the current ramps up to that peak, never exceeds it.

Now to determine what exactly the OP has. The YMM or Yr Make Model along with the exact location and function it was used in said vehicle would go a long way to determining what exactly we are talking about, or a picture of the device.

A few key points about solenoids. They often have a single wire and ground through their mounting. If they do have 2 wires one of them is usually black and/or is connected to the body someplace near the device. It will only actuate in one direction. There is usually some sort of spring that will return it to a resting position. Push it in and it will spring back.

A motor will always have two wires. When you manually move the rod/lever you can hear and feel the gear train and making the motor move. The rod or lever will stay where you leave it. It can provide force in two directions.

Solenoids do have their uses in automobiles but since they only provide force in one direction their use is limited to releasing trunks, hatches, fuel doors and things of that nature. Also note for things like a trunk or fuel door leases solenoid you'll typically find the circuit protected by a 20a fuse. No it probably doesn't draw anywhere near 20a but I'm betting it is more than 1a worth. In other words if it is a solenoid then it probably isn't legal.