1960 Power Top Micro Switches

[Joe M.]

I knew that I would reach this stumbling block, just didn't know when. I need some assistance with making the micro switches open/close at the right time.

I tested the deck lid micro switches and what is always open is open and what is always closed is closed. When I push the arms and activate both switches, it closes what was open and opens what was closed; as it should.

The problem seems to be with the micro switches located beside the seat pillar. The sides that should be open are closed and the sides that should be closed are closed. When I disconnect the wiring harness, both micro switches operate as they should. Sides that should be closed are closed and sides that should be open are open. When I trip the switches, the open sides close and the closed sides open.

I thought this condition meant there was a short in the wiring harness, so I removed the wiring harness and installed a second wiring harness; same results as before.

Can anyone help me understand what is happening on the seat pillar micro switches?

[Joe M.]

Re: 1960 Power Top Micro Switches

I was concerned that I would not receive a response to my questions. The only people that can answer the questions and fix the problems do it as a paying hobby and it is too rare an option for the NCRS members in general to help out. I understand that.

When I removed the original motor/pump 10 days ago (ordered a new motor/pump), all of the solenoids worked and cylinder rods raised and lowered. Ten days later the solenoids are not being energized and the rods don't move up or down. I ordered a new main wiring harness, but have no confidence that it will fix the problem since the main wiring harness worked just fine 10 days ago. At least I will have ruled out a defective main wiring harness.

My lesson learned with this project to date is that I should have purchased a unit that was already bench tested and ready to bolt on and watch it work. I am $500 below that price right now and the unit does not work properly.

[Dan B.]

Re: 1960 Power Top Micro Switches

Joe that is frustrating. I've never personally worked on a power top, but that would not stop me from trying if i were in your shoes. I see there is an excellent wiring schematic in my 59 AIM (60 is similar) on the Power top. My first thought is that your wiring harnesses are not bad but something is incorrectly connected or you have a bad switch somewhere. Study the diagram and get a test light to confirm the 12v hot and cold connections and with patience I think you can find the problem. Good luck Dan

[Joe M.]

Re: 1960 Power Top Micro Switches

it is not from lack of trying. I have been working on and off for 5 weeks to make it work right. Started checking individual wires today and I am using the wiring diagram in ST-12 (same as in 1960 AIM). I must be missing something, but haven't identified it yet. The underdash toggle switch may be part of the problem. There is no 12V going to the wires that energize the solenoids. I tried to hook up the wired directly to hot 12v source and the solenoids are not being energized. I have checked the operation of the 4 micro switches and the two safety switches and all appear to be functioning as they should. I am almost out of wires/switches to test with no solution.

[Terry M.]

Re: 1960 Power Top Micro Switches

Just a WAG here, as I have no experience with this system -- but any chance you are missing a ground connection?

BTW: While I was Restorer Editor (1999 to 1005) I had a story from a member about his efforts with a C1 power top. I am thinking it was on an earlier car than yours. Could have been a 57, but don't hold me to that. It might be worth looking into though.

[Joe M.]

Re: 1960 Power Top Micro Switches

Not missing a ground connection as I am using neg side of 12V battery on my work bench. John Hinckley wrote an article about a 1958 car with power top. I traced continuity from the fused power wire on the toggle switch to the solenoid, but when I flip the toggle switch, 12V never reaches the solenoid. I used a jumper wire to go directly from the toggle switch to the solenoids and made the cylinders operate up and down. I have gone as far as I can go with it. If new wiring harness does not fix the problem, and I doubt if it will, I will have to send it to one of the two men I have found that can make the units work.

[Terry M.]

Re: 1960 Power Top Micro Switches

Joe, the article I am thinking about was written by the car owner, not John. I remember the car being black and he did his PV at a Regional in Wildwood, NJ.

[Joe M.]

Re: 1960 Power Top Micro Switches

I have the Restorer CD and will search for it. Thanks.

Upon further analysis, I did have a missing ground; since I had the motor grounded directly to the battery, the solenoids were not grounded. I ran a jumper wire from battery negative side to the solenoids and all solenoids are working. I am making some progress. Although the wiring diagram in the ST-12 is very detailed, I had to draw out the individual circuit routes to visualize them better. For the top up process, I can raise the deck lid cylinder, followed by the folding top cylinders, but not able to get deck lid cylinder to lower at that point, but I now know which closed micro switch does that. A bit of optimism has creaped into the process!