Steps: Modify Outside Air Step Wiring

By Barry and Cindy 1997 U270 36′

Modify outside air step wiring to allow step to retract when the ignition is off

I also have modified outside step wiring to allow steps to retract when the ignition is off. I did it for security reasons and have used it several times. It prevents someone from stepping up to look indoor window. And makes a parked Motorhome less inviting and secures the small storage behind the outside step when folded up. And in a confined parking situation, it makes step-less vulnerable to physical damage.

One may also want to install a ‘kill’ switch to prevent a quick engine start if the ignition is jumpered. One could prevent battery current from reaching ignition switch via a ‘kill’ switch if a more secure situation warrants it.

The 3-way step air control valve on our 1997 U270 is powered when the ignition is on. This 12-volt ignition power feeds through the magnetic door switch to retract step. With ignition on, if the screen door or main door is opened, the magnetic door switch is opened, air valve de-energized and step will lower. When the 3-way air valve does not receive 12 volts, it feeds air pressure to air cylinder to force outside step open. When the 3-way air valve receives 12 volts, it feeds air pressure to the other side of the air cylinder to force outside step closed. When the ignition is off, the air valve is de-energized and step stays open, no matter what position the magnetic door switch is in.

To retract step when the ignition is off, supply 12 volts to magnet door switch to simulate that ignition is on. When the screen or door is opened, the magnet door switch will open to the lower step so we don’t fall on our face when leaving the coach. The step will NOT change from open to close and back to open if the front brake air tank is depleted.

In this situation, step can easily be physically moved to closed or open position and will stay in the position.

HOW TO MODIFY WIRING

To modify the outside step circuit, I found wire ‘C11’ leading to the magnetic door switch. I mounted an inexpensive single pole double throw switch.

The switch does not have a center-off position. I cut wire ‘C11″.

I connected cut wire that goes to the magnetic door switch to the center pole of the switch. I connected another side of the cut ‘C11’ to one of the side poles of switch. I then connected a house battery hot wire to another side of the switch. This circuit modification will not interfere with normal coach operation. It will be another small constant draw on the house battery when the ignition is off and switch is in a modified position.

I hope this helps to explain how outside step works on our coach and is an aid for you to design a modification that works for your coach.