1972 Backup Light Switch
Thread Starter
Racer
Joined: Mar 2007
Posts: 271
Likes: 0
From: Honolulu Hawaii
1972 Backup Light Switch
So bubba got into my Corvette. I actually have a toggle switch to turn on my backup (reverse) lights. So in short, I have to shift into reverse, then manually flip the toggle switch to turn on the backup lights. Then when I'm done backing up, I have to flip the toggle switch back off. Retarded much? 
Anywho, I got under my car and I see the backup light switch on the transmission. What I don't see is the wire coming off of it. The wires are clean broke off of it. I also don't see any wires hanging down from under the Vette where it would have broken off. If anyone has pictures or a good description of where I can find the other end of this wire 'connection'.
My other issue then is to eliminate the toggle switch so that it's no longer in the equation. This could be a nightmare.
Anywho, I got under my car and I see the backup light switch on the transmission. What I don't see is the wire coming off of it. The wires are clean broke off of it. I also don't see any wires hanging down from under the Vette where it would have broken off. If anyone has pictures or a good description of where I can find the other end of this wire 'connection'.
My other issue then is to eliminate the toggle switch so that it's no longer in the equation. This could be a nightmare.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Should be quite easy, locate the pink and green wires. They should be right outside on the firewall about where the throttle cable comes out. These two wires go to the backup light switch. Hook them up to the backup switch and they should be working .
Team Owner
Joined: Sep 2006
Posts: 31,170
Likes: 4,245
From: Westminster Maryland
Hi i,
G's right on.
The switch on the trans had a long pig-tail that reaches almost to the firewall grommet that has the tach cable, oil pressure line, and back-up light connector coming through it.
You can just see the plug-in connection in this picture.
Regards,
Alan
G's right on.
The switch on the trans had a long pig-tail that reaches almost to the firewall grommet that has the tach cable, oil pressure line, and back-up light connector coming through it.
You can just see the plug-in connection in this picture.
Regards,
Alan
Thread Starter
Racer
Joined: Mar 2007
Posts: 271
Likes: 0
From: Honolulu Hawaii
Thanks a lot guys, I found it when I opened the hood. The picture was perfect! That area right there is definitely pretty tight. Later I'll try to follow the wire down and see what I can come up with. I went under the car and found a pink wire cut and spliced back together and a black wire just cut and not spliced back together. This could get interesting....
Thread Starter
Racer
Joined: Mar 2007
Posts: 271
Likes: 0
From: Honolulu Hawaii
TCS Switch... What does that do? Must not be to too important if I haven't noticed 
Something else I found also was a cable on the drivers side of the transmission. Doesn't look like it has anything to do with the transmission, but the cable is broken and it looks like it was suppose to be going further to the rear of the car. I followed the cable up to the engine bay, and it looks like it connects to the steering linkage maybe? It's actually a little further down the firewall in Alan's picture. Not only is the cable broken under the car, the cable isn't hooked up inside the engine bay.
Something else I found also was a cable on the drivers side of the transmission. Doesn't look like it has anything to do with the transmission, but the cable is broken and it looks like it was suppose to be going further to the rear of the car. I followed the cable up to the engine bay, and it looks like it connects to the steering linkage maybe? It's actually a little further down the firewall in Alan's picture. Not only is the cable broken under the car, the cable isn't hooked up inside the engine bay.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
The cable is the steering interlock. The car has to be in reverse on a stick shift car or park in an automatic car for the key to be released. This cable attaches to the transmission linkage and to the steering column.
The TCS is a crude smog system in the early C3 casrs. It has to do with the timing and when to activate it. The car had to be in 4th gear for the vacuum advance to come in if I remember correctly. The blaco wire plugged into a switch on the 3/4 shifter arm. Most if not all have been disconnected.
The TCS is a crude smog system in the early C3 casrs. It has to do with the timing and when to activate it. The car had to be in 4th gear for the vacuum advance to come in if I remember correctly. The blaco wire plugged into a switch on the 3/4 shifter arm. Most if not all have been disconnected.
Thread Starter
Racer
Joined: Mar 2007
Posts: 271
Likes: 0
From: Honolulu Hawaii
The cable is the steering interlock. The car has to be in reverse on a stick shift car or park in an automatic car for the key to be released. This cable attaches to the transmission linkage and to the steering column.
The TCS is a crude smog system in the early C3 casrs. It has to do with the timing and when to activate it. The car had to be in 4th gear for the vacuum advance to come in if I remember correctly. The blaco wire plugged into a switch on the 3/4 shifter arm. Most if not all have been disconnected.
The TCS is a crude smog system in the early C3 casrs. It has to do with the timing and when to activate it. The car had to be in 4th gear for the vacuum advance to come in if I remember correctly. The blaco wire plugged into a switch on the 3/4 shifter arm. Most if not all have been disconnected.
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Thread Starter
Racer
Joined: Mar 2007
Posts: 271
Likes: 0
From: Honolulu Hawaii
Quick verification. Obviously this is the correct part because it looks just like it under the car, but the actual wiring doesn't look long enough to go from the transmission up to the connection in the engine bay. Anyone replaced one, and where did you buy it from? There's multiple websites with it.
Thanks guys!
http://ecx.images-amazon.com/images/...500_AA300_.jpg
Thanks guys!
http://ecx.images-amazon.com/images/...500_AA300_.jpg
Team Owner
Joined: Sep 2006
Posts: 31,170
Likes: 4,245
From: Westminster Maryland
Hi i,
Yes, that's the back-up light switch that mounts on the transmission. The wiring is about 2 1/2' (?) long. Many of the larger vendors sell it.
The TCS switch on the transmission senses what gear the transmission is in. In 70 & 71 the idle speed was increased in both 3rd an 4th gear, in 72 it was increased in just 4th gear.
Regards,
Alan
Yes, that's the back-up light switch that mounts on the transmission. The wiring is about 2 1/2' (?) long. Many of the larger vendors sell it.
The TCS switch on the transmission senses what gear the transmission is in. In 70 & 71 the idle speed was increased in both 3rd an 4th gear, in 72 it was increased in just 4th gear.
Regards,
Alan
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Hi i,
Yes, that's the back-up light switch that mounts on the transmission. The wiring is about 2 1/2' (?) long. Many of the larger vendors sell it.
The TCS switch on the transmission senses what gear the transmission is in. In 70 & 71 the idle speed was increased in both 3rd an 4th gear, in 72 it was increased in just 4th gear.
Regards,
Alan
Yes, that's the back-up light switch that mounts on the transmission. The wiring is about 2 1/2' (?) long. Many of the larger vendors sell it.
The TCS switch on the transmission senses what gear the transmission is in. In 70 & 71 the idle speed was increased in both 3rd an 4th gear, in 72 it was increased in just 4th gear.
Regards,
Alan
Cruising
Joined: Jun 2012
Posts: 10
Likes: 0
Hi Alan My recently acquired 1972 coupe didn't have a reverse light switch attached. I got one and looked for the plug to install it, but nothing was coming through the firewall. Where do they start, and are they pink & green from the beginning? Also this was an automatic converted to a manual trans. Are the wires still the same color?
Last edited by mmoore289; May 16, 2015 at 06:11 PM.
Team Owner
Joined: Sep 2006
Posts: 31,170
Likes: 4,245
From: Westminster Maryland
Hi mm,
On automatic cars the backup light switch is mounted on right side of the shifter assembly….under the shifter console.
It's part of the neutral safety switch. So that's where the connector will be. You'll need to determine where the lead goes from there.
I'd look there for the connector and then make a harness just long enough to reach through the firewall and to the connector from the 4-speed back-up light switch on the transmission.
Good Luck!
Regards,
Alan
On automatic cars the backup light switch is mounted on right side of the shifter assembly….under the shifter console.
It's part of the neutral safety switch. So that's where the connector will be. You'll need to determine where the lead goes from there.
I'd look there for the connector and then make a harness just long enough to reach through the firewall and to the connector from the 4-speed back-up light switch on the transmission.
Good Luck!
Regards,
Alan
Racer
Joined: Jan 2014
Posts: 407
Likes: 14
From: Mulberry Florida
Alex I'm glad you posted this because I also had no backup lights. After reading others replies i checked this morning and found the wires coming out of the fire wall were not hooked up. Now I have to get the car up enough to be able to get under it and find the wires coming from the switch and see if I'm able to connect the wires.
Again thanks for the post
Larry
Again thanks for the post
Larry
