Simple Bluetooth Camper Jack Control

My 5th wheel camper has electric jacks to raise and lower the front. When it is time to connect up to my truck the 5th wheel pin on the camper has less than a 1" up or down window where you can back up and actually connect to the 5th wheel in the bed of the truck. I can get it close before backing in however most of the time I'll need to get out and raise or lower the camper slightly to be able to back in completely.

So I built a Bluetooth solution to raise and lower the jacks using my Android phone.

Note: I am not including steps for building the Android App. There are plenty of helpful video's out there using the MIT App Inventor, which is what I used to create a simple app with two buttons the UP button sending a "1" and the down button sending a "2". The Bluetooth button actually connects the app to the Bluetooth device.

Attached is the App that can be loaded onto an Android Phone

1. 1- Wemos D1 R32 (ESP32) controler (Or any other ESP32 controler would probably work just fine.
2. 1 - 5V 2 Channel 5V Relay Module
3. 1 - 9 volt battery box (or some other kind of power supply to give the ESP32 and relay module the needed power.
4. 4 - male to female Dupont jumper wires
5. 2 - 5 pin SPDT Automotive Relays

I will be adding a power weather proof switch to the power cord on the battery box that will be mounted on the camper.

Attached is the code I created.

Using the Dupont jumpers make the following ESP32 -> Relay Module connections:

1. 5V -> VCC
2. GND -> GND
3. GPIO13 -> IN1
4. GPIO14 -> IN2

I made a slight modification to my original design as the 5 volt relays were not quite robust enough to run the 12 volt motor on the camper jacks. So only one of the 5 volt 2 relay modules is needed.

My camper has DPDT rocker switch to raise and lower the jacks by switching the polarity as shown in "DC Motor Reversing Switch." I disconnected the wires going to this switch. There were two wires going to battery and two wires going to the motor. (The two going to the battery had jumpers so as to reverse the polarity.)

I wired the two SPDT automotive relays as is shown in the picture above "Reversible DC Motor using 2 SPDT Relays."

Each of the two automotive relays had a black and white wire used to activate the relay. The white wires were attached to the ground of the battery. One black wire went to the "Raise" terminal of the DPDT rocker switch that was already mounted on the camper and the other black wire went to the "Lower" terminal. The middle terminal of the switch was connected to the positive side of the battery effectively turning that switch to a SPDT as I am now only using one side of the switch. This made the camper switch function in the same manner as before. Only the switch is now operating the correct automotive relay and not the motor directly.

I then wired one of the 5 volt relays in parallel with the "Raise" terminal of the camper switch and the other relay to the "Lower" terminal so that those two relays activate the two Automotive Relays also.