Trailer lights – testing continuity in wiring

I know enough about electric to be dangerous – so in the youtube videos I see that my multimeter is working fine, its set right to test continuity. It reads 1 with nothing hooked up. In the videos I see that if the wire is good it should read close to zero or at least hopefully less than 1. I did get that for some wires of the set up – but when I test at the plug closest to the lights I get readings above 2. I dont think the posts from the multimeter have a very good connection – I can only stick the metal probes into the male plugs and wiggle them around. Does this mean the circuits are ok? If there was a break what would it read? Thanks

There’s a difference between continuity and resistance (measured in ohms).

Continuity is a yes or no. You either have the flow of current through a conductor or you don’t. On most multimeters, a 1 indicates an open circuit, in other words there is a break in the conductor. A 0 indicates continuity. Some meters have an audible beep to indicate continuity.

Ohms is a measurement of resistance to the flow of current through a conductor. This is a more sensitive measurement that can indicate a variety of things from bad splices, corroded connections, a poor ground, etc.

Depending on what problem you are trying to diagnose, it may be better to measure DC voltage at various points. You need to have at least 12 volts along the entire run of wire, front to back. If any point you test is below 12 volts, there’s a problem there that needs to be found.

It sounds like you may be confusing continuity with the measuring of resistance.

IMO, if you are trying to chase down a broken wire, a test light is the go-to tool. You connect the trailer lights to the vehicle and then use the test lamp’s needle-sharp end to test the wire at various points to determine where the break is. Find the point where the current disappears and between there and your last good test point, you have a broken wire. I just find these tools faster and easier to use than a multimeter for this function and they are all of $5 at the auto parts store.

Grouse

If all the lights are acting funky then check ground as that is the usual culprit.