Tool to power specific electronics in a car not running

[727G35]

I'm going to a junkyard for a piece to electrically move my seat, I'd like to save time and money by getting a working part my first time.
I was wondering if theres somekind of tool like a voltage reader, except it puts power to the wires so you can hear if that specific electronic is starting.. I mean really I can use a 9v battery and wires right? I just was wondering if theres a name for a tool that does that

[727G35]

I was thinking 9v battery attached to a commecter that attaches to the leads

[PapaSmurf2k3]

Just bring a jump pack. Unhook the battery on the car (so it doesn't suck down the juice of your jump pack), and then connect your jump pack to the terminals on the harness. This should give power to the whole car.

[MinisterofDOOM]

Yep, I have a couple portable battery chargers I use for this stuff. Make sure you take some good wire cutters and some decent gauge wire in case you can't get to the factory terminals. I had to pull a trunk lid from a Lincoln LS once. Battery (and terminals) are in the trunk. Folding seat releases also in the trunk. Trunk was closed, and I didn't have a way to cut the main harness or large-enough gauge wire for the kind of amperage involved, which would both have saved me a lot of trouble.

[MinisterofDOOM]

Yep, I have a couple portable battery chargers I use for this stuff. Make sure you take some good wire cutters and some decent gauge wire in case you can't get to the factory terminals. I had to pull a trunk lid from a Lincoln LS once. Battery (and terminals) are in the trunk. Folding seat releases also in the trunk. Trunk was closed, and I didn't have a way to cut the main harness or large-enough gauge wire for the kind of amperage involved, which would both have saved me a lot of trouble.

[727G35]

Awesome thanks for the advice I have a jump box I think it only gives power when cranking tho not sitting idle.
I took an old 18v ryobi battery connected terminals with alligator clips so if jump box dosent work I'll try that. Just figured they should have something like that already.

[PapaSmurf2k3]

Yeah you're right... you'd have to have the key-on to get all functions with the jump box hooked up.

[IanS]

Get yourself a Power probe.

WAY more useful than a multimeter when it comes to testing 12V stuff, and you can easily plug it into a jump pack and test any 12 device on the car if you know the wiring diagram. I actually own 2.