LPU WB2907

The LPU's used with PTP600 and other models has a solid RED LED on its printed circuit board. The circuit board has PWR silkscreened next to the LED. I have verified that the LED indicates the LPU sees power coming from the PIDU. Can  this LED blink in certain conditions? What are the conditions? I have never seen it blink, but a field tech says his is blinking RED. I cannot find any information on this LED.

That's a mystery. There is no circuit in the LPU that is supposed to make the LED blink. It's a simple power indicator.