Ask Dave: Batteries won’t keep steps working. And where is the charger?

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. Today he explains RV house batteries and helps to troubleshoot why an RV’s steps aren’t working

Dear Dave,
I have a 1997 Allegro Star. The house batteries won’t keep my steps working. Is it the solenoid or charger for the house batteries? Also, does it prevent the generator from working? Is it time to replace both house batteries? Where is the charger for the house battery located? Do the batteries need water or…? Thanks. —Ellie

Dear Ellie,
Great questions! Grab a cup of coffee or beverage of choice and hunker down. This might take a while!

I’ll have to make assumptions without specifics

To provide more specific troubleshooting information, I need to know what type of batteries and how old they are as well as the type of distribution center/charger you have. But I can make a few assumptions.

Your 1997 Allegro probably has a Kwikee double- or triple-step setup that runs off the house battery. I would also assume that the house batteries in your unit are not original, so I’m not sure what setup you have. Possibilities are two or four 6-volt batteries or two 12-volt deep cycle and either lead-acid, AGM, or lithium. I’ll assume they are 12-volt lead-acid. You can tell by looking at the top of the battery. If there are three fill holes, they are 6-volt; six fill holes, they are 12-volt; and no fill holes, they are AGM or lithium.

How the Kwikee step works

The Kwikee step is activated by a door switch that could either be a plunger-type or magnetic. This is located at the lower right-hand side of the door frame. As the door is opened and closed, it tells the motor to extend or retract.

These are typical step magnets that create an open and closed 12-volt electrical connection. However, the plunger type has a switch in the inside frame that the door pushes in to activate. These have been a source of failure as the door actually pushes the plunger sideways before pushing it in straight. This bends the plunger every time the door is shut and eventually it will fail. That is why almost everyone switched to the magnet as there is no physical resistance. So, first, I would make sure your switch is not broken.

Let’s take a look at the house batteries

Even if your batteries are not good, the converter/charger of your rig should provide enough power to operate the steps if you are plugged into shoreline power. Here is another assumption: You probably have an all-in-one distribution center/converter/charger. This system has 120-volt power coming into circuit breakers for the 120-volt components such as the roof air conditioner, refrigerator on 120-volt mode, outlets, and other items. It also has 12-volt automotive fuses for the 12-volt components such as lights, roof vents, water pumps and other items like your steps.

Also in this configuration is the converter, which is the battery charger, and is typically located to the right behind the grill and has a fan with it. If you do not have the grill and fans, you might have a separate converter located underneath cabinetry somewhere. Winnebago started using a standalone converter from Magnatek in the mid–1990s, as the converter is noisy and gets hot and they did not want it in the living room or bedroom. If you do not have the grill and fan, we need to contact Tiffin to find out where it is located, although we may not need to find it – just check the batteries for charging.

Lead-acid batteries

If you have lead-acid batteries then, yes, they do need distilled water added if the acid level is below the plates. This should be a maintenance item that should be done at least once or twice a month depending on how you use the rig. To check the batteries and charge, use a multimeter set on the DC setting and put the red probe on the positive post and black on negative. A fully charged battery should read 12.6 volts. Plug the shoreline cord into a 30-amp supply. If the batteries are low, the converter should supply a 13.6-volt charge to the batteries. If you have a multistage charger this will be much higher, such as 14.4-16 volts, which is a desulfation charge designed to break up sulfation on the battery plates. When the battery reaches the 12.6-volt charge stage, your converter should taper off to 13.2 volts as a maintenance charge.

If you get a 13.2-volt reading at the battery with the shoreline cord plugged in and the steps do not work, there is something wrong with the steps. One thing that I have found in the older units such as yours is the distribution center could be underpowered and not providing enough charging power to the batteries. What happens is, if you have several 120-volt components running, your rig will have a high amp draw and there won’t be enough power to charge the batteries sufficiently.

I remember one year we had a model that would drain the batteries even when plugged into a 30-amp service because there were too many “high-profile” appliances and gadgets. If you have less than 13.2 volts when plugged in, try adding a portable battery charger and see if the steps work.

It might be something wrong with the steps

If they don’t work with the booster or when plugged in with 13.2 volts, then there is something wrong with the steps, not the batteries. At this point we need to verify the fuse is good in the distribution center and there is actually 12-volt power going to the step motor. The first thing I would do is open the door and listen for the motor to try and start. You should also see a light come on. If it does, it could be a weak motor or seized pivot points. Kwikee recommends lubricating all moving joints with KwikLube at least once a year. If not, then you need to verify 12-volt power at the module and probably need to remove the steps to bench test them. Hopefully, it’s something upstream of this.

And last, let’s consider the generator

You probably have an Onan generator mounted in a compartment towards the back of the unit that is started by a switch inside or on the generator powered by the house batteries. Once again, if the batteries are dead, it will not turn over but it should when you are plugged into shoreline power.

Use at least 30-amps for testing

NOTE: It is important to verify all this with at least a 30-amp supply. I have had several owners plug into a 20-amp supply in their garage, which is not enough power.

If the generator will not start when you are not plugged into 30-amp shoreline power, check the batteries or plug the unit in and verify voltage as described before. If it will not start when plugged in and you have verified voltage at the battery, check the circuit breaker in the distribution center. I would also try starting it from the switch on the generator, as well. If it still does not start, you need to verify 12-volt power at the generator itself.

I have a friend that is a pilot and right about now he would tell me, “David, land the plane already!” Sorry for the long post but I get paid by the hour (joking). It just takes quite a bit of verification on all the components and hopefully this gives you a path to troubleshoot as far as you feel comfortable. Or it gives you enough information to discuss it with a technician to let them know what you have verified and save some diagnostic time. It really hurts taking a unit into a service center only to find out it was the circuit breaker as they still charge you to flip the switch!

Good luck, and let us know what you find. And feel free to post any questions or concerns along the way. We have a huge readership that has taken this same journey as you are about to.

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