Looking for Ignition Switched 12V in Engine Compartment
Thread Starter
Racer
Joined: Mar 2005
Posts: 294
Likes: 1
From: Racine Wisconsin
Looking for Ignition Switched 12V in Engine Compartment
I am interested in adding an accessory to the engine comparment that is powered only when the ignition is in run. According to the schematic there are two 12v sources in the engine compartment that are swithched by the ignition switch. One is brown that goes to the alternator. I presume that it is the power to the coil. When I probed with the key on but the engine off, that connector was about 4.7v. With this indication this connector may be wired in series with some resistors or diodes in the alternator and I am hesitant to attempt to power anything else with it. According to the schematic there is another wire that is a black and pink that comes from the ignition switch to someplace near the distributor but not the coil. I am not able to find that one. The car is too old for GM running lights otherwise I would use that. Any suggestions from the forum.
Thanks
Thanks
Le Mans Master
Joined: Jan 2006
Posts: 8,319
Likes: 7
From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
Originally Posted by 7T3C3TTZ07
I am interested in adding an accessory to the engine comparment that is powered only when the ignition is in run. According to the schematic there are two 12v sources in the engine compartment that are swithched by the ignition switch. One is brown that goes to the alternator. I presume that it is the power to the coil. When I probed with the key on but the engine off, that connector was about 4.7v. With this indication this connector may be wired in series with some resistors or diodes in the alternator and I am hesitant to attempt to power anything else with it. According to the schematic there is another wire that is a black and pink that comes from the ignition switch to someplace near the distributor but not the coil. I am not able to find that one. The car is too old for GM running lights otherwise I would use that. Any suggestions from the forum.
Thanks
Thanks
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by 7T3C3TTZ07
I am interested in adding an accessory to the engine comparment that is powered only when the ignition is in run. According to the schematic there are two 12v sources in the engine compartment that are swithched by the ignition switch. One is brown that goes to the alternator. I presume that it is the power to the coil. When I probed with the key on but the engine off, that connector was about 4.7v. With this indication this connector may be wired in series with some resistors or diodes in the alternator and I am hesitant to attempt to power anything else with it. According to the schematic there is another wire that is a black and pink that comes from the ignition switch to someplace near the distributor but not the coil. I am not able to find that one. The car is too old for GM running lights otherwise I would use that. Any suggestions from the forum.
Thanks
Thanks
Thread Starter
Racer
Joined: Mar 2005
Posts: 294
Likes: 1
From: Racine Wisconsin
Thanks for the advice. I didn't think of the wiper. Obviously it only works when the key is in the "run" position. I'll try that with a relay. If necessary contort myself and crawl under the dash.
Racer
Joined: Jul 2004
Posts: 276
Likes: 0
...just make sure you don't pull high load on the wiring.
Using the switched line for a relay is one thing, running fans and other things off 30+ year old wiring is just asking for trouble.
I just got done doing my dual spal install, I used the wire at the coil as the switched, and ran dedicated lines back to the battery.
Using the switched line for a relay is one thing, running fans and other things off 30+ year old wiring is just asking for trouble.
I just got done doing my dual spal install, I used the wire at the coil as the switched, and ran dedicated lines back to the battery.
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