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Discussion Starter · #1 ·
Hello,

I have a '73 Opel GT. I changed out my ignition switch the other day and went for a drive. When I stoped to fill it up and got back in it would not start. My husband push me and I was able to jump start it from there. We decided the alternator was bad and installed a GM one with more amps. The problem is that when we connect it to the battery it acts as if it I have the key in and turned on (radio, electric fuel pump comes on) all the while I have the key in my pocket. I'm not sure if I wired something wrong with the ignition switch and it didn't show up because the alternator was bad or If I wired something wrong with the alternator. Any help would be appreciated!
 

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Need more info. .....a photo of the alternator you installed and how you wired it would help.
 

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Sounds like you miss-wired the connections at the white connector. The connector should be wired so that the colors connect. That is, the red wire on one side connects to the red wire on the other. There is one exception: the gray wire from the ignition switch connects to the Brown/White wire on the other side of the white connector. You should have the following wires coming down from the ignition switch: Red, Brown, Gray, Black, Black/Red. Miss-connecting these wires will produce the results you are exhibiting.

For what it is worth, there is a misprint on page 1J-93 of the 1973 Factory Shop Manual. It identifies the ignition switch steering column connector as "black" when it should be shown as white, as shown on page 1J-107, the full schematic in color..
 

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Discussion Starter · #4 ·
Sounds like you miss-wired the connections at the white connector. The connector should be wired so that the colors connect. That is, the red wire on one side connects to the red wire on the other. There is one exception: the gray wire from the ignition switch connects to the Brown/White wire on the other side of the white connector. You should have the following wires coming down from the ignition switch: Red, Brown, Gray, Black, Black/Red. Miss-connecting these wires will produce the results you are exhibiting.

For what it is worth, there is a misprint on page 1J-93 of the 1973 Factory Shop Manual. It identifies the ignition switch steering column connector as "black" when it should be shown as white, as shown on page 1J-107, the full schematic in color..
Sounds like you miss-wired the connections at the white connector. The connector should be wired so that the colors connect. That is, the red wire on one side connects to the red wire on the other. There is one exception: the gray wire from the ignition switch connects to the Brown/White wire on the other side of the white connector. You should have the following wires coming down from the ignition switch: Red, Brown, Gray, Black, Black/Red. Miss-connecting these wires will produce the results you are exhibiting.

For what it is worth, there is a misprint on page 1J-93 of the 1973 Factory Shop Manual. It identifies the ignition switch steering column connector as "black" when it should be shown as white, as shown on page 1J-107, the full schematic in color..
Audio equipment Computer hardware Gadget Electrical wiring Electricity
 

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I apologize -- I made the assumption that you still have the original connectors down under the steering column. From the picture, I see you have the Black/Red and the Red wires connected correctly. However, it appears that you have connected the Black wire possibly to the Black wire that runs to the fuse block and to the Brown/White wire. This is incorrect. According to the wiring diagram, the Brown/White should connect to the Gray wire coming out of the harness from the ignition switch.

Something that confuses me is that I see the Gray wire coming out of the harness, is connected to another Gray wire that, according to the wiring diagram, does not exist! Is that indeed a Gray wire, or a White wire, and can you tell where it goes after the connection?

Something to understand about Opel wiring:
Red is used for all unswitched power from the battery
Black provides switched power. In this case, Red offers power to the ignition switch and the Black wire is bringing switched power to the ignition system and accessories (the Black/Red wire provides switched power to the starter solenoid).
Brown is always a ground on Opels.

As to the alternator, there are three wires that travel over from the voltage regulator, that plug in to the alternator. It is possible that the terminals on your new alternator are not consistent with the OEM product. But tracing from the voltage regulator:
Red should connect to the D+ terminal on the alternator (the Light Blue/White wire travels back to the charge indicator bulb on the ammeter)
Black should connect to the DF terminal
Brown (ground) connects to the D- terminal.

Hope this helps
 

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Discussion Starter · #6 ·
I don’t have a brown/white wire
I apologize -- I made the assumption that you still have the original connectors down under the steering column. From the picture, I see you have the Black/Red and the Red wires connected correctly. However, it appears that you have connected the Black wire possibly to the Black wire that runs to the fuse block and to the Brown/White wire. This is incorrect. According to the wiring diagram, the Brown/White should connect to the Gray wire coming out of the harness from the ignition switch.

Something that confuses me is that I see the Gray wire coming out of the harness, is connected to another Gray wire that, according to the wiring diagram, does not exist! Is that indeed a Gray wire, or a White wire, and can you tell where it goes after the connection?

Something to understand about Opel wiring:
Red is used for all unswitched power from the battery
Black provides switched power. In this case, Red offers power to the ignition switch and the Black wire is bringing switched power to the ignition system and accessories (the Black/Red wire provides switched power to the starter solenoid).
Brown is always a ground on Opels.

As to the alternator, there are three wires that travel over from the voltage regulator, that plug in to the alternator. It is possible that the terminals on your new alternator are not consistent with the OEM product. But tracing from the voltage regulator:
Red should connect to the D+ terminal on the alternator (the Light Blue/White wire travels back to the charge indicator bulb on the ammeter)
Black should connect to the DF terminal
Brown (ground) connects to the D- terminal.

Hope this helps
Thank you! I will rewire and see what happens!
 

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Did you ascertain that the new alternator is correctly wired in?


Going back to the ignition switch connection, the car originally had two connectors for the harnesses coming out of the steering column. The ignition switch harness ended at a white connector that plugged into a socket on the side of the fuse panel; a similar black connector was next to it, connecting the horn wire and turn signal circuitry. I will assume that a previous owner eliminated the white connector, either running replacement wires or connecting the harness directly as you have done.

Again:
The Red wire coming out of the fuse panel is delivering power to the ignition switch and to the turn signal switch (via the second red wire on the ignition switch that runs to the T/S switch).

The Black wire carries power from the ignition switch (only when the switch is "On") for the ignition system and accessories.

What I thought was a Brown/White wire that you have connected to the Black wire, that loops up over another harness to a connector, may in fact be an accessory added by a previous owner, possibly the electric fuel pump. Still, that would not cause the symptom you describe, so long as the ignition switch is in the "Off" position.

The Black/Red wires are connected correctly

That leaves the Gray wire, and, again, I do not recognize the wire it is connected to.
 

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Certainly shows what it looked like from the factory, but, as evident from Sue's picture, someone took apart the white connector connection and dug into the fuse box to pull wires and make individual splices. It could take a bit of work to pull all of that out to determine if the proper connections were made.

I am wondering also if the key lock unit was put in correctly? It has been almost fifty years since I took apart a steering column on my first GT to replace the ignition switch, so I do not recall, but is it possible to install the locking mechanism in such a way that the switch remains "On" when it otherwise should be "Off"? Just a thought.
 
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