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Eureka! I found part of my problem. Pulled the center gauge out and started testing connections one at a time using my homemade tester (see pick of 9v) and some of the awesome images/diagrams you all provided. I learned that my number 9 ground connector was blown. When I looked closer, it should have been obvious (see red circle in pic). That doesnt solve my issue of lack of power to the power windows though, does it?
Homemade tester..... not the best, but it worked. This should have been so easy to see!
Good Eye on that broken ground path!
Now onto the power window problem. The power window relay has 2 sources of power, Coil power (IGN Cavity Plug) and Switching power (ACCY Cavity Plug) on the fuse panel. The power window relay gets it's grounding by it being bolted to the to shift consol frame support, check if you get a good ground at the relay.
Here is a good video from Mr. Willcox on testing the relay.
I also see you have a bulb socket in the LOW FUEL light hole, after replacing circuit board if there is a bulb in that socket it will be on when the ignition is on. If you have a empty bulb socket there just to keep junk out, good for you!
Link to all pages of the 77 ETM: http://www.europeancorvette.com/html...l_diagrams.htm P.27
Last edited by bmotojoe; Apr 21, 2020 at 07:06 AM.
I got all of my electrical issues resolved; so a huge thanks to all of you! I'm not 100% sure what fixed the power windows. I replaced the circuit board on the gauge cluster so that fixed all of those issues. I then pulled the power window relay out to test it. When I reinstalled it, the windows worked great. My only thought is that somehow the ground was not making good contact and when I reinstalled, it had a better contact. Either way, problem solved! Time to move on to the next improvement! Thanks guys!
