Can someone email me a Wiring diagram for a 72 SB Automatic.

I have one that i am using now in one of the popular books, but I have to flip between different pages that cover all 68-82 c3's and it can be somewhat confusing to decifer.

Ken, at one time I think you said you had the wiring diagrams

It can be emailed to me at mattheld@holley.com

 

After Shark38405.3083680556

______________

I will send it to you tonight.  Just need to get home and settle in front of the computer.

if you send it tonight. send it to my home account.

matthew.held@netzero.com

 

thanks Ken

______________

Done.

Thanks I got the info.  Now on to other questions.

I have looked at three different wire diagrams and can not find this connection anywhere so here are some questions that maybe someone can help me with.

I have a plug need the center console that I can not figure out where it goes or if something plugs into to it.  I believe its for a seat belt warning buzzer relay.  But I cannot find it on any schematic.  Its a wide 2" plug.  On one side is two wires going to a single spade. Wire colors are Black w/Tan Stripe and Yellow w/Black Stripe.  On the other side is two wires leading to a single spade.  Both wires are Pink w/white stripe.

another Question:  On certain plastic connectors with two wires in them there will usually be one side of the connector both spades are fully protected by the connector.  The other side will have the spades exposed by little scalloped cut outs.  So my question is does it matter how these get plugged back in.  One case if the wiper vacuum solenoid under the dash.  does it matter which wire goes where?

Same thing but this pertains to the gas pedal.  First off what is this electrial switch attached to the gas pedal?  Its plastic and has a slider going through it sorta of like a restat.  It has a plug for a plug with two wires.  I belive the enter from the engine side off the engine harness.  The wire color s are orange and Tan.  Is that correct?  Also does it matter which way it gets plugged in?  I believe this is somehow tied to the TCS (temperature Controlled Spark) Solenoid.  I no longer have this option so can I just leave it unplugged?

Lastly.  On the engine harness there is a thick red wire that is terminated with a plastic single spade positioned at the wiper motor location.  I know the Blue and Yellow connect to the wiper pump.  I know the RED with Wite Strip plug to the Red/white stripe for the wiper limit switch.  I also know the black spade goes to ground and the Three wire connector connects to the wiper motor.  But where the heck does this other red wire go?  It looks like it would be a power wire to the wiper motor.  I have looked at two schematis and one shows it connected to the wiper motor the other schematic does not show it at all.  I have inspected the old harness and based on the color of the spade have come to the conclusion it was never connected and I can find no connection for this at the wiper motor.

Any help would be greatly appreciated.

______________

Sorry, I haven't been on for a couple of days.

The plastic slider on the gas pedal is for the kick down on a Turbo 400 transmission.

As for the other questions, I will take a look at the diagram myself and get back to you.  Once I see some of these, I may know what the others are for.

Red wires are always hot, but could be switched by the key.

Orange wires are always hot, but feed accessories such as interior lights.

(I just corrected my earlier statement, the 72 is a bit different in some colors.)

I'll get back to you.

kstyer38406.4039930556

Interesting....turbo 400.  I need to look again I could have sworn my car had a turbo 350.  I have no wires going to the tranny.  I should know its out right now.  Only the vacuum modulator.  I know its not the numbers matching engine.  I could have swore my care was a turbo 350 car.  So am I correct about the wires going to the slider, orange and tan coming off the engine harness through the firewall?  Does it matter which wire goes to which side?  I guess it really doesn't matter since a 200R4 is going back in.  I guess I could just leave it disconnected.

Any help would be be great help.  I'm going back over to the shop tonight to continue the wiring work.

 

______________

My 75 has a turbo 400.  Sometime in 76 they switched to the 350.  You may have a 350, but it appears to have been swapped.

One at a time.

The plug in the center console is either a seat belt warning or alarm system.  Maybe. I don't see it on my diagrams either.  Often in older cars they did not show some options or acessories on some of the diagrams.  My best guess at this time.   I will keep looking.  Some of my newer diagrams may provide a clue.

the plastic connectors do have the cutout on one side.  Those line up with a tab on the metal spade connector, or should.  If you look at the spade term, you can see a small depression on one side, and a raisied section on the other side.  The raised side goes to the side of the plastic with the cutout.  If it is a two wire solenoid, it probably won't make any difference in operation.  Most of these are not polarity sensitive.  A three wire connector or more is critical.  Other wise the wires are mismatched to the device.

The slide on the gas pedal is for the kickdown on the Turbo 400.  It also ties in with the spark control.  You have neither, so don't worry about them. 

That red wire does have me lost at this time.  Many GMs used a wire like this to supply power to the high speed blower relay.  Has the a/c been changed or removed?  Again I will keep looking, and perhaps I can see something on a newer diagram that will apply.  I'm guessing it's hot all the time.  If everything functions in the car,  consider something that may have been removed in the past.

Ok, here is what I have found out so far after a lot of research.

I found on M&H Fabricators website that they offer a 72 harness with ac w seatbelt warning buzzer and without the buzzer.

I was able to find the wiring color information that matched the wiring on my car, but it was on a schematic for a 73.

I also found the wire colors for the kickdown and have confirmed they are orange and tan.  According to the 73 schematic, I need to match the wire colors on the other side of the switch, tan to tan, orange to orange.  I guess that would tell me which way all of the plugs get connected.

The wiper motor is another story.  On 72 schematic it shos the red wire on the engine harness connecting to the wiper motor.  I have check three different publications and all show this to be the same.  In one book, they even show an place on the circuit board where the red wire is suppose to be connected.  They show it to be on the inside and it has to be soldered on.  However I don't see a place for the wire to exit.  On the 73 wiring diagram they show no connection for the red wire.  so I'm still at a loss.  I',m going to make some phone calls to see what I can figure out.

 

 

______________

Perhaps a 71 diagram.  I'll look when I get home.

Ok, I got it all figured out.  Had to call some experts, so I called one of our sponsors, Bairs.  Talked to their body guy Mike that does there restorations.  Turns out their should be a red wire on the wiper motor.  The entire system will not work without the wire connected.  The red wire routes through the limit switch to ensure the wiper door is open before the wiper motor comes one.

Well I think that wraps up this forum post for me.  Next.

______________

With not wiper door on the 73 that does make sense.  My guess is you have a late 72.  Glad you found the info.

Another strange thing I found.  I actually believe it was a hack job by the last owner.  I had this large orange wire with black strip that ran from the center console area through the fire wall to what I blielieve is a relay or fuse.  One side was label AUX the Other BAT.  The wire was connected to the aux side and another wire ran from the BAT side to the Horn Relay.

After studding lots of wiring diagrams it turns out the Orange wire with the black stripe actually goes to the power window relay at the console.  But according to the wiring diagram that orange and black wire should be plugged into the ACC port on the fuse panel.  I'm not sure why it was run outside, but everything ab out the wire lookd factory, including the wire running from the horn relay.  I can't find anything that shows this wire going to an outside fuse/relay.  So I wired it as show in the wiring diagram.

I should have it correct, I will know more once I get some other things wired up so I can test everything.

______________

If you have a wire that you think would go to a shoulder belt that is very possible on a 72.  I was looking on the NCRS post the other day and they talked about the shoulder belt having a buzzer.  This would be on a later 72.  The seat belt code was C15.  So if you have a shoulder harness coded C15,  then you would have a wire for the buzzer.  I seriously doubt that this is on the wiring diagram as it was a mid-year change.  This may not affect you, but I was in a talking mood.

Mark