Amp Draw

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
washtubman

washtubman

Well-known member
Joined
May 14, 2007
Posts
119
Location
Anderson, Indiana
I need help from one of you battery/electrical experts.  My chassis battery keeps losing charge.  The battery is good.  Here's the situation:  When I check the amp draw at the battery with the cutoff switch on the coach in the "OFF" position, I get 0 amps as expected.  However, when I turn the switch ON, I am reading almost 17 amps!  There is nothing on in the coach.  I pulled the fuse to the step motor and checked the amp draw and it was down to almost 0.  Put the fuse back in and the amps went back up.  Neither the step motor or the wiring are warm and the step operates perfectly as it should.  What the heck could be causing this large amp draw????  This is on a 2005 Holiday Rambler vacationer.  Thanks for any input or ideas.
 
Since the draw goes away when you pull the step fuse, the problem is in the step circuitry.  It's fairly common for the relays on the control board to develop rough spots that can keep them from disengaging when they should - i.e. to shut off the power to the motor when the step is fully retracted.

Try tapping the relays with the step all the way in and see if the draw goes away.

Or the in limit switch could be bad, again not telling the board to turn off the motor when the step reaches it's limit of travel.
 
A coach will have phantom draws. Clocks, radio memory, propane detectors and step solenoids. I know my previous coach had an air operated step, but the solenoid was charged all the time
 
I agree with Lou that relays can continue to draw if the contacts don't open all the way.  The tap method may assist in finding the relay if that is the issue.

Also, make sure to be absolutely positive that the step IS the draw.  What I mean is has someone added something and tapped into the step circuit.  Measure the amperage directly at the step and see if you are getting the high amperage (I think you said 17 amps).  If you are getting the 17 amps at the step/relay then you found your problem, if not then see where the circuit branches off to something else. 

Mike.
 
Could it be possible that the step is not going all the way to the stop, is something stopping the travel. I once had a rug on the step that would not let the step go all the way in.
 
If you have the Kwickee steps you will have two (2) connector plugs (one is a 2 pin and the other is a 4 pin plug). I would disconnect them, one at a time, to see if high current draw goes away. The 4 prong connector goes to the electronic module ( I think the relay is contained in the module) and the two way connector goes from the module to the step motor. If the high amp drain is still present with the 4 way connector disconnected then you will probably be looking for a ground between the main fuse for the steps and the 4 way connector.
Here is the website for the Kwickee steps owners manuals. Just click on the steps your coach has (my guess is you have the 888 style steps).  http://www.kwikee.com/Adocuments.html#steps

If you find you need parts (electronics module, motor, etc) you can go to your local RV dealer. I replaced the complete assembly (module, motor, and mechanical gear assembly). Kwickee (I think its now the same company that sells the Power gear jacks and slide stuff) will not sell to individuals.
 
Here is an update to the situation.  If I unplug the step motor connector, the amp draw is almost zero.  With it plugged in, the draw rises to 17 and then after about 10 seconds, comes back to .01 and stays there.  Before I didn't leave the probes on that long, so only saw it rise to 17 and didn't see it come back to .01.  So, do I have a problem or not (rhetorical question)?  I don't have a relay for the step, apparently it is built into the electronic control module and there is nothing in the way of the step to keep it from going all the way in or out.
 
As I understand the step operation, that is no problem. Basically the motor cycles and quits when it finds it cannot move the step any further. Whether it is full in, part in, or full out.

So you are back to square one on your battery problem - the step isn't draining it.  Some so-called phantom load is normal - it's a full amp in my coach with its dozens of electronic gadgets. How much is it in yours?
 
My Winnebago's "automatic" compartment lights have a habit of not turning off when the door is shut. Not always the same compartment and real hard to adjust as you obviously can't see the light go out. The only way to tell if they are all out is checking amp draw. Luckily there is a switch next to the entry step that kills power to all compartments. I just have to remember to make sure it's off.

Typical draw if one is left on is 4 amps.

I intend to replace the button switches with manual toggles. Figure if I have a hand free to open the door, I'll have one free to turn on/off the light.

 
washtubman said:
My chassis battery keeps losing charge.  The battery is good.  Here's the situation:  When I check the amp draw at the battery with the cutoff switch on the coach in the "OFF" position, I get 0 amps as expected.  However, when I turn the switch ON, I am reading almost 17 amps!
Click to expand...
I'm not familiar with a Winnie's wiring systems, but the OP says his problem is his chassis battery and when he turns off the cutoff switch on the coach he gets zero amps.  So, if the "cutoff switch on the coach" is for the coach (house) batteries, could it be his problem is the emergency battery switch is stuck & holding house & chassis batteries connected?
 
Good News!  Although my battery is good, apparently it just needed a long charge.  I put it on the charger for 12 hours at 10 amps before going on our first camping trip of this year.  We were camping 4 days and the chassis switch was left "on" all the time.  Battery stayed at 12.6 volts all the time.  Guess the temporary amp draw from the steps had nothing to do with anything.  I'm a happy camper!  Thank you for all the replies.
 
A trickle charger is a helpful item to have attached to your chassis battery when camping or in storage, to keep the battery topped off and ready to start the engine any time.
 
You must log in or register to reply here.

Latest posts

Members online

Total: 879 (members: 6, guests: 873)

Forum statistics

Threads
131,973
Posts
1,388,457
Members
137,722
Latest member
RoyL57
Back
Top Bottom