Nm, is this a serial data lift? Is the HC-CIO the electrical isolation for the lift computer, or just the button module? My thinking is, if it isn't serial data I would try to swap the individual floor level trailers to the these floors to see if the fault moves to another level. If it is serial data, then it should use this for communication from the car control pcb(car top isn't it?) to the controller. Maybe that cable is getting noise or induced voltages or maybe the car control pcb is faulty. The fact that you have already changed the HC-CIO pcb, tends to think this isn't the fault. From what I remember the buttons aren't individually coded so have you tried changing the button modules or wiring in case this makes a difference? Anyway food for thought.

check your travel cord,an car station something is taking those calls to ground.

Is the car sitting still or moving when these calls latch? If the car is moving, which direction? If moving, does it latch when the car passes at the same point in the shaft?

Disconnect you position indicator wires for 4 and 5. See if that stops the phantom latching?

Switching wires on the board as well as unplugging the wires on the board is a good idea to be 100% sure that the issue is in the controller, wished I'd thought of it sooner. There is no pattern to the calls latching; the car could be idle, running up or down, top or bottom of the hoistway, with or without passengers etc. The reason I didn't go after the traveler yet is because even if the call signal goes to ground, three other buttons (in the correct sequence) would also have to ground.

By the way, I did call MCE and they were not full of ideas. They suggested checking for power supply issues (mainline to mainline) and looking for sources of induced voltage.

is it a single car, or in a group? if it is in a group, check to see if the communication LED on the swing panel for the car you are having trouble with is going out intermittently. If the led goes out, and the car is not communicating to the group, it will start going into a wild car type mode, where it will automatically register car calls and stop at those floors, and continue until the communication is re-established. worth a shot, i had a bad ribbon cable from the comm port board to the swing panel in the car, and the group comm led was out, it would just register random calls until i replaced the cable. just another idea. good luck

Is the call dropping when it gets there? or staying on? I have had a lot of issues on a new job with induced voltage. I have also learned to ask for Chris at MCE he is a very sharp guy, even If you have to leave him a message to have him call you back he is worth the wait. I have been mislead by others only to buy more parts it seems.

Have you tried wiring the car calls (4C, 5C) into the hall calls (4U, 5D) instead to see if the phantom calls still register?

A fellow mechanic also suggested looking for loss of communication, I did not see this occur.

Yes, the call drops. I did speak with Chris, he also suggested looking for induced voltage.

Should have a board tomorrow, so I will be going back to install the board and measure ribbon cables. I will give this a try.

ive had this happen on older turnbull and dover tractions. I had a bad power supply that was feeding the floor cards and it would drop just low enough to latch the call then stabilize. just another thought.

New HC-PIO board didn't do the trick. Removed the traveler wires from the input terminals where my phantom calls are latching, calls still latch.

Got a good guy (James) from MCE technical support. After lots of poking around he suggested the same things that were mentioned here and by others I work with.

He had me check Bus 2 from controller to controller (ST2A to ST2B) in the group controller, they should read 60VAC or less between each other. I read 120VAC between the two, this indicates that the cars are out of phase with each other. This issue normally shows itself upon start up, apparently it can cause all kinds of oddball problems such as mine.

I ran out of time and didn't have the correct ring terminals with me today. When I go back Monday, I'll have to swap two legs feeding my main transformer until the cars read in phase. If this doesn't fix my issue, tech support suggested changing the MCCGDP board. I am going to order the board anyway.

Good find, phasing of each car in the group was somthing that used to be done regularly, I still did that when I was in the field. I advise the younger guys to do this when they Mod, even though most of the installation documents we see now don't address this anymore.

Hey e311, id like to understand this more. Is this only for the bus supply or for all supplies? I take it the group controller has an output for the bus to each individual lift controller. This would come from the original power supply to the group and then the pcb's split it where it is all needed. So are we just talking about +/- being reversed and thus 180 degree out of phase? What was your process for getting the cars in phase with each other, as I cant say I have ever had to worry about this?