Time to track down the AC issue. It's been elusive chasing this problem. So far I've done the following:
7/23 - took the shark to my mechanic. He converted the system to R134. He could get the compressor to kick in if he hotwired it but it would't start w/ the button on the console. (post #51)
8/23 - I find a really good thread on Rennlist where someone documents the steps trouble shooting electrical issues w/ the AC. It discusses a relay that's in the Central Control Unit (CCU) - the HVAC unit in the console. I replace the orig relay with a replacement relay. (post #52)
9/23 - 11/23 - take it back to my mechanic but still no juice at the button. I get her back and order a new AC button. Still no juice.
Decided to pick up the trail now to see if I can locate the issue. I reread the debug thread again.
https://rennlist.com/forums/928-forum/609038-hvac-compressor-relay-repair-procedure-w-pics.html
Start at the freeze switch, which is the first place the author starts. Using a test light, I have no juice coming into the freeze switch from what is supposed to be the hot wire. Check the switch for continuity and it checks out, so the switch is good.
Go inside and check the fuses and relays associated w/ the AC. They check good. I check the wires on the relay I replaced. They look like they track to the proper places. At this pt I started a thread on RL asking for help, but I've stumped the band.
I find a schematic and follow it but it doesn't make a lot of sense to me.
I tear the CCU apart and poke the 15 tabs with my test light. Tabs 1, 5, 7, 8, 10, and 15 were hot. When I turned the AC button off, 7 & 8 lost power. #6 wasn't hot and that was the problem. After more research I find the definitions of the tabs. 7 sends juice into the CCU for the AC clutch and 6 needs to send it out to clutch. The first stop is the freeze switch. Obviously not happening.
I send a PM to one of the shark gurus asking for ideas. He points me to a shark electrical guru who I PM. We email back and forth a bit and after thinking everything over, he suggests I recheck wire 6 from the CCU to the replacement relay. I track the wire from the motherboard to the relay and unscrew it. It looks like a 6 but it's very small. I unscrew the one next to it - it could be a 5 but hard to tell since it's so small. I grab the small magnifying glass I have but it's still hard to tell. Time to pull out the big gun - the magnifying glass my dad used when repairing vacuum tube radios and TVs.
It lit up when I plugged it in and hit the on button. Probably been at least 40 yrs since it been used as dad's been gone 37 yrs. But now I could see the post I thought was 6 was actually a 5. I put the wires in their proper slots and put the CCU back together. Plugged it in along with the AC button. Hooked up the battery, turned the ignition to ON, punched the AC button on. Then checked my test light at the freeze switch.
Success!
The clutch wasn't running, but I figure it won't unless the engine is running. I have the dash all torn apart - partly to chase down the AC issue and partly for the dash replacement. More on that to come...