Otis Elevator

Hi, I have a friend with an Otis residential elevator RES740 in his house. it's stopped working

It has an old Omron C20 C series PLC in it, the fault light was flashing (he hadn't changed the battery in 20 years) He had Otis out to look at it, they knew nothing about it just sent him a huge bill.
Can someone suggest how to attach to the PLC, first of all I want to see if there's still a program in it, if not I will need to find one.
The owner says the PLC outputs are sometimes lit so with luck it has the EEPROM memory option.

Does anyone have a program for one of these old elevators, even if it's for a different PLC

The elevator is a 3 level hydraulic type.

Thanks
Roy

BTW I used to service the elevators at a hospital I worked at but that was before PLC

Roy,

I am surprised the c20 even works.
The C20 uses a handheld programmer and a I think it also uses a cassette tape
recorder to store the programs. I'm not sure, but I think the S6 programmer will work on it, note the words I THINK, it's been to many years since I programmed one.

If you google or use bing, You will need to know the exact model number of the unit. There were lots of units (new / used) for sale as well as a pdf manual. I typed in Omron c20.
regards,
james

James,
It's a C20 SYSMAC C Series, yes I see a picture of a terminal that screws on the front and the manual refers to using a standard cassette recorder.
The parts list calls for Omron CPU73E, Omron PS-222
I think I might be in luck, owner says the output lights come on which makes me think it might still have a program inside, the power was off for several weeks without a battery but I believe the CPU uses an EPROM to store the configuration.
Thanks for getting back.
Roy

Here is a link you might be able to get some info concerning the old Omron plcs. Be sure to scroll down the page and look at everything.
Link:
http://www.mikroe.com/old/books/plcbook/plcbook.htm

I believe I have a C20 programming module. I can't recall the model of it - PRO-01 or something - , but as I recall it is about 5" x 1" x 3", and has a DB-25 serial port on the front, and the back has the connector to clip into the C20.

I also have several C20 parts around.

Rob