Hope you had a great Thanksgiving. My problem is that my RV’s electric entrance steps do not work all of the time. I have had the step motor out and it runs fine on the bench but it will not work when hooked up. The fuse is good and the grounds have been freshened up. Help! —Paul
It could be the wiring, or since the electric step is typically powered by the house battery it could be a weak or sulfated battery. House batteries can be very tricky as they look to be fully charged at 12.6 volts but the minute you put a load on them they drop immediately.
Lubricate the hinges of the entrance steps
The first thing I would do is lubricate the hinges of the entrance steps thoroughly as well as the shaft bearings. According to Kwikee, who is the #1 manufacturer of electric steps and is now owned by Lippert, it is recommended to use KwikLube Spray Grease. You can get it here.
They do not recommend WD-40 or silicone lubricants. However, I have used Fluid Film before as it is a great rust inhibitor. These steps get pretty abused so they tend to rust easily.
If you still have a problem with the entrance steps not working, hook up a battery charger to boost the house batteries to see if that helps. Since your motor works on the bench, it seems like there might be a combination of a little resistance from the actual steps and a weak battery. If the boost doesn’t work, then it’s in the wiring somewhere. I would suggest taking the grounds off and connecting them directly to the battery negative to verify a good ground.
Check electrical connections
Even though you may have cleaned up a ground connection at the step, there may be a hairline crack in a weld somewhere that opens and closes with temperature changes. Also, check all electrical connections to ensure they are dry, protected, and not compromised. Most electrical connections are the automotive-style plug-in type and are fairly well-protected from the elements. However, the wires inserted in the back of these connections can start to pull out and get exposed to water and corrosion. Also, since the step has several moving parts, wires can get pinched and either exposed to corrosion or have an open sheathing that can touch a metal ground.
This is the main wiring harness for a Kwikee Step we recently worked on. Even though there is an automotive-style plug and corrugated protective tubing, the wire connections on the back of the plug are exposed. Kwikee recommends a dab of dielectic grease at any connection and heat shrink tubing at any butt connections. I also recommend tracing all wiring to ensure there are no kinks or crimps. Wire tie any loose wiring to the holes typically found in the step frame to keep them out of the way of moving parts.
What is unfiltered electrical power from converter?
I have been in the RV industry since 1983, and it seems I learn something new almost every day. Something I learned while researching this further is unfiltered electrical power from the converter. Here is the verbiage directly from the Kwikee Service Manual:
“The step may also operate erratically if it is operating directly from a converter and the converter output is not adequate or properly filtered for clean DC voltage. The converter must be capable of producing a minimum of 30 amps for proper step operation.”
What this means is if your house battery or batteries are dead, sulfated, or have a bad cell, the converter in your rig is providing the 12-volt power. Depending on your model of converter/charger, it could mean your converter is not capable of providing sufficient power to the rig for all operations.
I often use a term in troubleshooting called “gremlins.” That’s a term for those annoying failures that only happen while camping and can’t be diagnosed at a dealership during troubleshooting. It’s difficult to replicate the exact situations of what other appliances were being used so actual power usage, temperature, and other situations that caused the failure out in the field will not show up when you are sitting in a controlled environment at a dealership or at your home. This is why I recommend carrying a 12-volt booster so you can apply this to your batteries when the situation actually happens while camping.
Check entrance steps switch
One other item to check out is the entrance steps switch. Since you did not provide a make, model, and year, I do not know what type of step it is and if it has the old plunger-style step switch or magnetic one. Inside the door, there is an activation switch that opens and closes an electrical connection to the motor. Older models had a push-in type button or plunger. It would eventually get bent as the door swung around and literally pushed it sideways first, before getting square with the frame and pushing it straight in. This would cause the switch to malfunction, so Kwikee changed to a magnetic style that was limited contact.
There are several versions, as shown by the diagram in the Kwikee Service Manual.
Once again, if it worked on the bench, I would assume you did not have the actual door switch connected to it. You should be able to remove the switch and touch or “jump” the wires to verify if it’s the switch.
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Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club.
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