[Captain Midnigh]

1986 Partner 4 Centurian 4. Was working well. Overnight machine quite working. Reset button doesn't work. What is the first thing to check to get going again?
Thank you.

[chipsinpan]

You need to be a bit more specific .
Do you have any computer screen , or error messages ?
power to all the fuses ?

[Captain Midnigh]

Input power OK, fuses OK. No error messages. Very slight light on sceen, but no numbers or letters. 24 volts to relays. What is my next thing to check?

[chipsinpan]

I'm no expert , but I can relate from personal events :
if the monitor was burned out , you'd probably still get a flashing reset light (unless its burned out ) .
The computer is not communicating with the control .
On my cent 5 , there is a regulated power supply that feeds 120 vac into the control . This box is below the main computer box and has 2 outlets on top . you can pull out the plugs one at a time and just jumper them to an extension cord plugged into the wall and see if it powers up the computer .
One of these cord powers up a cooling fan and the other goes to a power supply inside the main box . If this yields no results, then the next step would be the power supply inside the main computer box .
You have to take off the cover ( 8 small screws ) to get to the power supply unit . Similar to a computer pow box , it converts 120 vac to 12vdc.
and 5vdc. legend on that box will tell what terminals are supposed 12v.
there are 2 flat plugs P8 & P9 that plug onto the circuit board . this is where to check for voltage . b carefull!

[Captain Midnigh]

I Have a Cent. 4.

[chipsinpan]

Cent5 is all I am familiar with . maybe someone else can join in .
But I stand by my original generic advice that you have to determine if the computer is booting up or at least getting power . When you turn on the main power on a cent 5 , and look at the screen quickly , it says "no input signal " for just a few seconds , if the computer is not sending a signal .

[Captain Midnigh]

When turning on power, I get nothing on the screen but a faint background glow. No numbers or letters. Should I be checking power source supply?

[Captain Midnigh]

The 5 volt power supply seemed to be operating wierd. I pulled it out and it tested fine. When re-installed, wierd again. There seems to be a 1/2 volt feedback from the terminal strip feeding back into the power supply. Where would this voltage come from? The total voltage on the terminal strip is .78 volts instead of 5 volts. What next?

[Ben Colby]

Check your cycle start button. Mine went bad and it caused havok with my CRT and it
caused programs to E-stop all over the place.
Check your E stop button, the control may be coming up in e-stop.
Check your control/keyboard for any stuck buttons.
When you power up with the front control consule open, can you see your CRT tube
getting power? I apply contact cleaner on the ribbon connector once or twice a year.
I also have to clean the wire connectors on the back of the tube occassionally.
I get alot of corrosion problems where I live on the southwest Washington coast.

You don't say if you are getting power to the servos after pushing reset?

[Captain Midnigh]

No power to the servos. I have tapped all the console buttons to unstick them, nothing. There is a faint glow on the monitor, but no picture. I'll open up the console, and check buttons from back side.