1972 TCS Circuit

[Scott K.]

My 1972 350 Auto had it's TCS solenoid removed and wires cut.
Not uncommon.
Putting things back to original & have a couple of questions.
Also not uncommon

a few weeks back, when repairing my high speed blower relay, I came across an "extra" orange wire. Obviously, it's not extra and belongs somewhere.
Now that I'm putting things together, I've found three other wires that belonged to the TCS (see pic)



And here's a pic of what it should look like connected...
(courtesy a distinguished member with a very nice 72..)



What I didn't find is the 2nd tan wire. The three I did find are perfect matches for the ones in picture 2. Yes, I'm missing the connecter, but looks like Doc has that part in his .pdf catalog.

Based on a drawing I found in the Haynes Chevy Shop Manual on page 208, it references a "Trans Control Kickdown Sw" that has .... an orange wire going to it and a tan wire leaving it to the TCS.



If I'm reading this correctly, if the car still has this Kickdown, perhaps the tan wire is nearby and the orange just needs to route there. If it's missing.. well, then we'll deal with that.

Where exactly would I find the Trans Control Kickdown Switch?

Someone here must have been there done that.

Hope I'm on the right track..
Scott

[Jim T.]

Re: 1972 TCS Circuit

My 1972 350 Auto had it's TCS solenoid removed and wires cut.
Not uncommon.
Putting things back to original & have a couple of questions.
Also not uncommon

a few weeks back, when repairing my high speed blower relay, I came across an "extra" orange wire. Obviously, it's not extra and belongs somewhere.
Now that I'm putting things together, I've found three other wires that belonged to the TCS (see pic)



And here's a pic of what it should look like connected...
(courtesy a distinguished member with a very nice 72..)



What I didn't find is the 2nd tan wire. The three I did find are perfect matches for the ones in picture 2. Yes, I'm missing the connecter, but looks like Doc has that part in his .pdf catalog.

Based on a drawing I found in the Haynes Chevy Shop Manual on page 208, it references a "Trans Control Kickdown Sw" that has .... an orange wire going to it and a tan wire leaving it to the TCS.



If I'm reading this correctly, if the car still has this Kickdown, perhaps the tan wire is nearby and the orange just needs to route there. If it's missing.. well, then we'll deal with that.

Where exactly would I find the Trans Control Kickdown Switch?

Someone here must have been there done that.

Hope I'm on the right track..
Scott

My 70's kickdown switch is just above the gas pedal.

[Edward J.]

Re: 1972 TCS Circuit

Scott, my 72 air car has that orange wire cut and taped (pass. side), that was a factory cut. just the tip of the cut wire shows and the rest is taped up.Not sure of what it was used for maybe something to with another engine or opition.

[Rich C.]

Re: 1972 TCS Circuit

Could that Orange wire be the feed for the heater blower on non A/C cars,(part of engine harness). When a car had A/C the separate A/C wiring harness provided power for blower (then orange was cut and taped). The orange wire that goes to transmission switch for TCS (on automatics anyway, is usually a fairly small guage wire that drops down transmission tunnel on drivers side.

'73 LS-4 454 owned 21 1/2 years

[Pete B.]

Re: 1972 TCS Circuit

My 71 auto had an extra wire dont remember color, it was for a stick shift car for the clutch interlock switch..obviously not used in an automatic application.

[Scott K.]

Re: 1972 TCS Circuit

Scott, my 72 air car has that orange wire cut and taped (pass. side), that was a factory cut. just the tip of the cut wire shows and the rest is taped up.Not sure of what it was used for maybe something to with another engine or opition.

Ed,

Thank you for this reply.

I noted that this wire has no voltage to it (tested it back when I was redoing my Hi Speed Blower relay).

So.. if I take this "out" of the equation and set it aside, that leaves me with two dark blue-ish wires and one tan.. all destined for the TCS switch on the pass side of carb.

Do you have the TCS in place or are wires cut? Either way, if they're accessible, do you have two blue and two tan or just three?

Thanks -

Scott.

[Scott K.]

Re: 1972 TCS Circuit

Could that Orange wire be the feed for the heater blower on non A/C cars,(part of engine harness). When a car had A/C the separate A/C wiring harness provided power for blower (then orange was cut and taped). The orange wire that goes to transmission switch for TCS (on automatics anyway, is usually a fairly small guage wire that drops down transmission tunnel on drivers side.

'73 LS-4 454 owned 21 1/2 years

Rich,

Good info. Noted. I have an AC Car. The only other "Orange" is the one that comes from the horn relay via the fusible link. I've accounted for that one since it's connected and working.

The way that wire was compressed in a Z pattern and is a heavier gauge wire than the TCS and since it's physically longer than everything else may indicate what everyone is saying.. an extra wire in the harness.

For now, I'm thinking this is the case and will see what other's have to say otherwise.

Thanks again.

Scott.

[Scott K.]

Re: 1972 TCS Circuit

My 70's kickdown switch is just above the gas pedal.

Thanks Jim.

[Edward J.]

Re: 1972 TCS Circuit

Scott, will take a look tomorrow, I will have to move my 63 which is parked under the 72, which is on the lift.