Wiring Diagram for the Replacement Electric Jack Switch with Harness # LC387874

Question:

Do you have a wiring diagram for this switch

asked by: Tom

Expert Reply:

Yes, I have attached the wiring diagram of the Replacement Electric Jack Switch with Harness # LC387874 for you to reference. Basically the Blue wire goes to a 6A auto reset breaker, like part # LC134181, which then goes to the positive circuit for extending, the Yellow goes to the positive circuit when retracting, the Red wire goes to the positive battery terminal, and the Black wire goes to the negative battery terminal.

expert reply by: Jon G

click to enlarge

Anibal

7/24/2024

Hi Jon. I have a Lippert smart jack on which the "smart" components got wet and ceased to function. I bought a simple extend/retract switch and bypassed the "smart" components. It works but keeps blowing a 6A fuse that I put between the blue wire and the red motor power wire. It's just a regular fuse, not like the auto reset one that you illustrate here. My question is, is this fuse needed and, if so, why? It didn't have one before. Thanks, Anibal

Jon G.

7/24/2024

@Anibal I haven't taken apart the Lippert Smart Jack # LC643589, but if there wasn't a fuse to begin with then you should be fine. Fuses are a good safeguard to keep from having to replace something more expensive if it gets too much power. As long as your bypass work isn't going to be overloading anything then the fuse you added won't be needed.

Anibal

7/24/2024

@JonG Thanks Jon. I ended up putting a 15A fuse in the holder and, so far so good. Appreciate your prompt response!

Jgh

2/1/2025

Hi could I use a dump trailer remote switch it has the up and down with 4 wires

Jon G.

2/3/2025

@Jgh You can certainly try it and see. I would say make sure you have circuit breakers in the appropriate locations to make sure everything is protected prior to trying this out though.

Rene L.

4/9/2025

Hello. What is the white ground wire doing on the switch?

Jon G.

4/9/2025

@ReneL Not going to lie, I'm a little confused by this question. If you have a white ground wire then you'll want to ground it for proper function... If you're referring to the diagram above, there is no white wire in the diagram, but the Black ground wire is connected to the negative battery terminal in this case.

Rene L.

4/9/2025

@JonG Hi Jon, regarding above question, white ground wire is going to one of the 4 terminals on my up/ down momentary 4 wire switch. The opposite terminal has the power ( red) wire. 3rd terminal is power down, 4th terminal is power up. What is the white grounded wire’s function? Thanks. and sorry for the confusion.

Jon G.

4/10/2025

@ReneL The white ground wire's function will be to provide a ground for the electric setup. If you notice in the diagram on the answer page above, this switch has a ground wire as well. All electrical components require a ground to work properly, so you'll want to make sure your white ground wire is connected either to the negative terminal on your battery, or a bare-metal surface on your trailer frame. It's best to follow the instructions from the switch manufacturer. If you don't have those then I recommend wiring your switch up to the same connections your old switch was connected to.