Well I figured out why my block heater stopped working. It started tripping the GFCI a while back, but I tested it and it ohmed out OK and the contniuity test was Ok on the cord. So I plugged it into a normal outlet. That worked for a while... ... until... ... ... . it finally quit altogether.
Just previous to the block heater going out I had to install 2 new grid heater relays as they were both not working. The wait to start light was coming on for the proper time, but it was not energizing the grid element. I don't think they both failed at the same time, could have been years apart. So I hooked up a LED to each element. Now the Wait to start light comes on and both LEDs light up. After engine start the LEDs will alternate coming on and off as the engine warms up. I always thought they both came on at the same times.
Just previous to the block heater going out I had to install 2 new grid heater relays as they were both not working. The wait to start light was coming on for the proper time, but it was not energizing the grid element. I don't think they both failed at the same time, could have been years apart. So I hooked up a LED to each element. Now the Wait to start light comes on and both LEDs light up. After engine start the LEDs will alternate coming on and off as the engine warms up. I always thought they both came on at the same times.