Kwikee step insights - MUST read.
First of all, many thanks to all the contributors here for their insights and advice. I have been diligently working away at resolving my Kwikee step malfunction, and after much testing and scrutinizing, determined that the motor and transmission were fine, but the control relays were turning on and off almost instantaneously but intermittently as well. Considering that was the last link in the chain, I started looking for a new control unit.
Shocked at the cost, I opted for replacing it with a manual switch so I wired that in and after much testing to determine that it was correct, I powered it up. Nothing. I could hear the motor trying to engage so I was back to thinking the motor was bad. I double checked the wiring and voltage was getting to the motor but it wasn't moving. I then pulled the motor off and tested it on the ground and it worked fine. When I rolled back underneath and tried to move the steps manually however, they were stuck solid.
Insert ah-hah moment here.
I determined that the linkage was pushing about 2 mm too far past the Apex and locking up against the housing, jamming the aparatues totally. The motor torque was unable to overcome the binding from the weight of the steps and the control unit was sensing the overload and causing the relays to cycle, so the control unit itself was not bad after all and neither is the motor.
There's a little bit of slop in the linkage but it still worked okay, not worth replacing yet. I would need to take off either the housing or the arm and weld a bead of material in that space to take up the slack, so I started making plans for that.
Insert 2nd ah-hah moment here.
Right at that moment, I noticed the adjustable cam stops on the step arms and they were at the thinnest point on the cam, so I adjusted those so that the arm didn't extend as far, and that stopped the pivot from passing the apex.
Rewired everything, tidied up the typical Friday afternoon RV construction wiring gong show, and sent it. Works perfectly!
If you run into this issue, try adjusting those stops first and see if it saves you from going through 8 hours of troubleshooting unnecessarily.
I wish I had taken a better pic of the layout before I reassembled it but I hope this saves even one person time or a grand in parts.
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