WC8 Green Light Stops Flashing

On one of my WC8 boards the green light on the board next to the red one stops flashing about 10 minutes after startup. It remains on solid, not blinking.
I would like to know the purpose for the lights, I can't find it in the manual.
I assume the red is indicating power.
The Network lights are working correctly, I can connect with it OK.
Thanks for any help.
 

The green light is heartbeat LED, indication CPU is operation normally when it blinked normally.
When the green light stopped, that indicate something went wrong with either the CPU or EEPROM chip.
Of course, the green LED itself could go bad, or its current limiting resistor could go bad, so that it is no longer blinking.
You can use a voltage meter to measure the voltage across it, if the voltage is up and down every second, that means the LED gone bad.
 
When you say everything working normally other than green led, it is possible the LED itself or current limiting resistor gone bad.

CAI_Support said:

When you say everything working normally other than green led, it is possible the LED itself or current limiting resistor gone bad.

Click to expand...

 
Surely a failed current limiting resistor or the LED itself would result in the LED remaining off/dark? The OP says it's ON hard...

You are correct Ross. If the board is operation, its green LED should be blinking. From OP, the board is working. so I am puzzled.

When I measure across D3 green led I get 1.39 to 1.41 vdc that is at about 1 sec rate. Following the trace up to R2 I get .16 volts steady across it. The green light will flash properly if you power down for about 10 seconds or more and come back up. About 10 minutes later it just goes solid and stays on. 
 I have tried it with a plc program and without and results are the same. It appears to work correctly or at least it is reading 3 temp sensors correctly and accessable thru network.
 
I am OK with it if it won't fail prematurely.
thanks for your support 

Are you saying when green LED is not blinking, the voltage across it reads alternate 1.4V and 0.16V? It would be strange the LED can stay on with 0.16V.

The voltage across the LED is 1.39 and goes to 1.41 and back to 1.39 at 1 second rate. The .16 is across the resistor that appears to be in series with the LED. With so little change in voltage across the LED it looks like it is on all the time. What ever is driving the LED appears to not make the proper transition from on to off.

LED is directly driving by one of the CPU output pins.  Supposedly the output is from logic 0 to logic 1, then back to logic 0, repeating forever.   1.39 is between logic zero and logic one. This might be an indication that output pin somehow having problem. 
 
If you purchased it within last 30 days, you can send back for replacement.  For CPU problem, the repair cost is higher than purchase a new one.

Unfortunately I bought on 2/13/14 from an ebay vendor so I assume the warranty is up.
 
Thanks for your support, I really like this product. I am accustomed to ladder logic but I am trying to learn this type programming. Some experience with Visual Basic.
I run a AB PLC here at home but like the ability to control it thru WC8 internet connection.

Normally any IO pin related issue only has 30 days warranty, because any user accident can cause IO pin damage.
However, for your case, we would extend that warranty to you, if you send it back, we will take a look and replace it, since this kind of problem we have not had before.

Thank you, Where did I need to send it to.
Max

You can send it to our web site street address under company->contact.
Please do include your contact information and ship to address for us to contact you.

When I thought I could not return it, I cut the trace to the green LED to stop the current drain and added a LED on an output to flash and let me know the program is running.
 I will get it in the mail, Monday.
 
Thanks again,
Max

Any modification will void warranty.  We are sorry about that.

After encountering networking problems with this particular WC8, I have to get off my network FOREVER.