Find Cut Wire With 9V Battery?

I have an 04 crown Victoria (ex police cruiser) and I'm trying to find where a particular wire was cut in the door (the wire ends at the door latch and goes to the LCM under the steering coloumn).

Basically instead of tearing everything apart to find the cut, I'm wondering if there's a way I can send a charge to the wire at the door latch with a 9 volt battery and test it with a probe or multimeter to the next easiest access point to the wire (ie. The door jamb or the LCM). The idea is that if I get a signal at the door jamb then I know the wire is not cut in the door but in the car.

Hopefully this makes sense. If this can work, I imagine I'd hook the ground up to a metal part and just use a posi tap to hook the positive terminal to the wire in question. Then test further down the line.

Any reason why this may or may not work? Thanks for any input.

It may work, but I wouldn't recommend it. I'd use a voltage/ohm meter to simply check continuity between any two points on the wire to locate the break in the wire.

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Oh wow, I'm a moron lol, I didn't realize I could simply do that with a multimeter. Kind of a noob with this stuff lol

Ha - weren't we all!

Many DMMs have a "Continuity Test"; I make sure mine include audible buzzer.
Continuity is usually when below 50 Ohms - it does NOT mean a short circuit.

I use Ohms when the multimeter has no Continuity test.


Of course, NEVER do an Ohms or Continuity (or Diode etc) test on a powered circuit; disconnect batteries etc.

Yea I'll probably go out and buy a multimeter with the buzzer to make my life easier lol. Thanks for the tips guys!

A test light might suffice, else be a handy addition - especially for things DMMs can't measure, or measure so easily & cheaply.

For once Peter I'm against using a test light here, this would be a CAN systems vehicle at this age in Europe so easier to stick with a DMM; you won't be injecting damaging voltage into the circuit( = damage = $$$)

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Thank you Master - I missed that subtle line "..at the door latch and goes to the LCM...

Of course that where oldFarts like me with my 1960s vehicles can be outright dangerous, or at least damaging.