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Opened up the headlight buckets to see if the micro switches were wired correctly. They were not. After a few hours, I have them wired to the correct positions on the micro switches. I have JJ Wheatley's wiring diagram and it is the best. Wired the micro switches using 71 factory service manual, wow, glad I don't have to use that any more. JJ's diagram is pretty straight forward for the micro switches in the driver's side bucket.

The issue I am having now is the passenger side bucket micro switch position. Does it go on the left or right side of the rotator ? The rotator has a place for two micro switches and I can't figure out if it goes on the left mount or the right mount when the rotator in in it's correct position. Sorry if this is a no brainer, but I don't want to take the buckets out a second time. (actually third).

Thanks,
Bob
 

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Discussion Starter · #3 ·
Norbert, exactly what I was looking for. Now I can start to put the bucket back in. The fun begins now. Thanks for the pictures, they really do say a thousand words.

Bob
 

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1970 Opel Gt - Purchased July 1972 - Chartreuse - restored - 3000 miles as of 02-16, 2021 -
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700 Posts
Opened up the headlight buckets to see if the micro switches were wired correctly. They were not. After a few hours, I have them wired to the correct positions on the micro switches. I have JJ Wheatley's wiring diagram and it is the best. Wired the micro switches using 71 factory service manual, wow, glad I don't have to use that any more. JJ's diagram is pretty straight forward for the micro switches in the driver's side bucket.

The issue I am having now is the passenger side bucket micro switch position. Does it go on the left or right side of the rotator ? The rotator has a place for two micro switches and I can't figure out if it goes on the left mount or the right mount when the rotator in in it's correct position. Sorry if this is a no brainer, but I don't want to take the buckets out a second time. (actually third).

Thanks,
Bob
I can't thank Norbertone for his contribution but I can thank you Bob. As you said a picture is worth a thousand words and these pictures will help me a lot. The beginning of the next project is off to a great start. Carl
 

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Opeler
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According to the schematics I reviewed and also working on two 1970 GTs and one 72 that I have, Opel changed the microswitch configuration possibly in 1971. 1970 configuration has two relay switches in parallel and one high beam switch and the later models only had one relay switch and two indicator switches and only one main relay switch. On the BubbaGump GT project I will be eliminating all three and replacing with a single double pole single throw lever switch on the backside of the headlight handle. Been wanting to do this for decades and now it will happen. I'll write up the mod with pictures when I get to that point......in a couple months.
 

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1970 Opel Gt - Purchased July 1972 - Chartreuse - restored - 3000 miles as of 02-16, 2021 -
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Mike, Maybe I will wait until you finish your modification before jumping into it. You seem to have a pretty good handle, no pun intended, on the subject of micro switches so a couple of questions. I know one of the switches is to signal the white dash light about lights not properly open or closed which to me is not a big deal as my white light never functioned in the 48 years I have had the car. Lights always closed and opened well, so seems like, to me anyway a function I can live without. Second question/comment before I rewired my lights which was just replacing the light wiring harness, my lights came on when rolled over, they now come on when I press the main light switch, so seems like that switch is also a none issue. Don't ask me how or why this happened but it works. I guess that leaves me with the one switch that sends power to the relay via the yellow black wire. Seems to be working OK. Actually I think I am looking for a way to avoid taking all of that stuff apart and putting it back together again. Just getting those buckets out is, well you know, but getting them back in, OMG.
 

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HMMM that is interesting Carl not sure of the difference between the 73's which I own and earlier models but I thought the light switch in the dash was only for parking lights and not the headlights. Do you remember when you replaced the Harness as you said if everything went back where it was pulled from? I'm thinking that maybe a wire was put on the same side of the circuit that controls the running lights only( if that make sense) another words is back feeding to the head lights?
 

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Opeler
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Yep, I'm actually an EE by degree although my job pulls me into mostly aero and mech these days. But I can explain at least the 1970 GT wiring which I believe is good for 70 and earlier. As mentioned these models use two "normally open" micro switches which are wired in parallel. One side of the switches (12 Red) is hot with key on. The other side (12 Black/Yellow) runs back to the headlight relay to turn it on if one or both headlight buckets are fully locked. Note the opposing terminal of the headlight relay is grounded so low current power runs from the fuse box terminal all the way to both buckets and back to the relay. Not sure why Opel used 12 gauge for the relay power as that is the low side. The third micro-switch is the "Ind SW" relay which is a "normally closed". This switch receives power from one of the terminals on the headlight relay when energized (12 white/yellow) wire. If the left bucket is not fully locked open, this switch will remain closed and provide power to the dash white light indicating that your headlights are ON but NOT locked in the open position. If the bucket is in the fully open and locked position then that switch will open the circuit and the dash light will go off.

In the later GT models the function is essentially identical but they went with one ON/OFF micro-switch and two IND switches. The system is great when it all works but if a switch goes bad it is a royal PITA to fix because you must remove the buckets, access panel in the wheel well, and the headlight rotator assemblies.

Hope this helps.
 
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Opel Key Master
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Mike, this is nothing new. 69 models only had micro switches on one side. 1970 had micro switches on both sides and the wires for the driver turn-on switch were also on the passenger side. They spliced right where the factory wires for the headlamps spliced. Then they switched the wiring in 71-73 which eliminated this. On all our harnesses we build for in house restorations, we will wire the headlights up like a 1970 so that if a switch fails, you will not know it unless the other one fails too. So no pulling headlights when one does fail, you have a backup. I have offered it in the past for people wanting a new harness.

Also the wiring for those switches can be dropped down to 20g wire, I like 18g due to it allows a little more wire to be crimped. This will give you a lot more room for routing the harness back, especially around the booster/master cylinder
 

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Opeler
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Keith, good to know and also glad you also noticed how Opel used 12 gauge wire for a primary side of a relay. 18-20 gauge makes much better sense!
 
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