Ignition (electrical) switch question.

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The Artist formerly known as Turbo84
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Trying to make sense out of the wiring diagram for our old C3 antiques. It boils down to this: In the actual electrical switch (at the bottom of the column), when the key/switch is in the cranking position, is the wire that feeds the ballast resistance (and coil C+) electrically hot? It would seem to make electrical/engineering sense to me that it would be hot in this position also, rather than only in the relaxed RUN position.
I've never had to take one apart, so I don't know the mechanical internals.
Thanks,
Mike
 
Jeebus man, you really testing my olde tyme antique mammory....I have to say YES it is....the feed to the resistor/coil + wire, OR HEI....fully knowing that extra terminal on the starter solenoid that jumpers it outta feed maybe renders it moot, BUT I remember not having a early starter in a car and it still started....resistor wire or not....so it HAD to be that way....

I would have to tear my dash back apart and see WTF, and I have some extra column switches to compare with....:amazed:
 
Jeebus man, you really testing my olde tyme antique mammory....I have to say YES it is....the feed to the resistor/coil + wire, OR HEI....fully knowing that extra terminal on the starter solenoid that jumpers it outta feed maybe renders it moot, BUT I remember not having a early starter in a car and it still started....resistor wire or not....so it HAD to be that way....

I would have to tear my dash back apart and see WTF, and I have some extra column switches to compare with....:amazed:

Well, electrically it just seems to make sense that the RUN mode circuit is hot while cranking. In the event of a crappy connectuon from the solenoid (shunting the ballast), there's be no ignition while the engine is being turned over otherwise. I've heard claims that the RUN and Crank circuit (connections feeding the coil C+ terminal) are time or key position independent, but that just doesn't make engineering sense to me. So, if nothing else, I was curious if anyone had a spare switch circuit that they could ohm out for me to answer this question.
 
Mike, I got extra column switches on the shelf for some years now, thing is, there is no wiring harness to give me a hint of the color codes much less wiring positions.....sorry I can't help further....would have been a LOT easier maybe 3-4 daze ago when I had my interior out....

sorry....:sos:
 
Does this help?
Wiring_101_5.jpg
 
Disconnect the solenoid ballast resistor bypass. I think you'll find the car starts. Mine had the wire broken at the solenoid and started fine.
 
Trying to make sense out of the wiring diagram for our old C3 antiques. It boils down to this: In the actual electrical switch (at the bottom of the column), when the key/switch is in the cranking position, is the wire that feeds the ballast resistance (and coil C+) electrically hot? It would seem to make electrical/engineering sense to me that it would be hot in this position also, rather than only in the relaxed RUN position.
I've never had to take one apart, so I don't know the mechanical internals.
Thanks,
Mike

Yes, they overlap.
 
Trying to make sense out of the wiring diagram for our old C3 antiques. It boils down to this: In the actual electrical switch (at the bottom of the column), when the key/switch is in the cranking position, is the wire that feeds the ballast resistance (and coil C+) electrically hot? It would seem to make electrical/engineering sense to me that it would be hot in this position also, rather than only in the relaxed RUN position.
I've never had to take one apart, so I don't know the mechanical internals.
Thanks,
Mike

Yes, they overlap.

That would make sense. I've been seeing some guys complain about their car not wanting to start until they relax the key back to the Run position (blaming a poor/open connection from the starter solenoid). This just didn't make good design sense to me if the the switch was designed so that there was no overlap.

Thanks for the input, guys.
 
Trying to make sense out of the wiring diagram for our old C3 antiques. It boils down to this: In the actual electrical switch (at the bottom of the column), when the key/switch is in the cranking position, is the wire that feeds the ballast resistance (and coil C+) electrically hot? It would seem to make electrical/engineering sense to me that it would be hot in this position also, rather than only in the relaxed RUN position.
I've never had to take one apart, so I don't know the mechanical internals.
Thanks,
Mike

Yes, they overlap.

That would make sense. I've been seeing some guys complain about their car not wanting to start until they relax the key back to the Run position (blaming a poor/open connection from the starter solenoid). This just didn't make good design sense to me if the the switch was designed so that there was no overlap.

Thanks for the input, guys.

Yeh, it's a adjustment on that switch to slide up and down the column, two 5/16 bolts, easy do without dropping the column even...
 
Mike -
This question only applies to engines with original points distributors - not engines with HEI or "Unitized" ignitions (anybody please e-mail me or let me know if you have a "unitized" system or if you know what it is...):

On points ignition cars, the circuits do not run in parallel. In the ignition switch (on the steering column), there is an "IGN1" and an "IGN2" contact point, and the two points are not connected. When you go to the "start" position, contact is made with the "IGN2" terminal. In this position, power to the circuit is completed through the starter's "R" terminal, and battery voltage is applied to the "+" side of the coil for start through the starter. When the engine starts and the switch is released, it flicks back to the "IGN1" position, and power to the coil is routed through the resistor wire. The two circuits are independent, and they do not run in parallel. On HEI and Unitized cars, the "IGN1" and IGN2" terminals in the switch are molded as a single "bar." If you have an HEI system ignition switch in your car, your engine will start without power through the starter. If you have a "correct" ignition switch in your points-ignition car, the engine will not start unless you have the complete circuit hooked up through the starter's "R" terminal.

Lars
 
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Mike -
This question only applies to engines with original points distributors - engines with HEI or "Unitized" ignitions (anybody please e-mail me or let me know if you have a "unitized" system or if you know what it is...):

On points ignition cars, the circuits do not run in parallel. In the ignition switch (on the steering column), there is an "IGN1" and an "IGN2" contact point, and the two points are not connected. When you go to the "start" position, contact is made with the "IGN2" terminal. In this position, power to the circuit is completed through the starter's "R" terminal, and battery voltage is applied to the "+" side of the coil for start through the starter. When the engine starts and the switch is released, it flicks back to the "IGN1" position, and power to the coil is routed through the resistor wire. The two circuits are independent, and they do not run in parallel. On HEI and Unitized cars, the "IGN1" and IGN2" terminals in the switch are molded as a single "bar." If you have an HEI system ignition switch in your car, your engine will start without power through the starter. If you have a "correct" ignition switch in your points-ignition car, the engine will not start unless you have the complete circuit hooked up through the starter's "R" terminal.

Lars

I converted my '69 distributor to electronic ignition in '74, so this question was just for curiosity.
I'm not following your description of IGN2. The only way it makes sense for me is if IGN2 is the starter solenoid (cranking) circuit, not any ignition function. Also, I interpret what you wrote about IGN1 is that it would be dead/open during cranking (ie: no start without the R terminal current). That doesn't make engineering sense to me (and conflicts with the general consensus above). What am I missing here?
 
You're not missing anything. On an ignition switch installed on pre-HEI GM cars, the IGN1 and IGN2 switch contacts are two separate contact points, and they are not connected at any time. Only one of the contacts at a time makes contact, and the other is always "open" whenever the opposite one is closed. Just take a look at the wiring diagram - the GM wiring diagram doesn't care what the other people in this post have a "censensus" about - there is a big, 1/2-page diagram of the ignition switch contacts and contact positions in the Service Manual. The year manual that is interesting is the 1972 manual, which actually shows the two different switches (points ignition versus unitized ignition) and their contact positions. The pre-72 Manuals only show the points type switch with the separated IGN1 and IGN2, and the 1975+ manuals only show the HEI type switch with the bridged contact points. Fact is fact. The ignition switch was revised with the advent of the Unitized ignition, and the Unitized switch was subsequently used on HEI. On this revised switch, the IGN1 and IGN2 individual terminals were bridged together, and the wire to the "R" terminal on the starter was eliminated. This switch operates the way you're thinking the switch should operate, but that's not the case with a "real" pre-HEI ignition switch.
Lars
 
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You're not missing anything. On an ignition switch installed on pre-HEI GM cars, the IGN1 and IGN2 switch contacts are two separate contact points, and they are not connected at any time. Only one of the contacts at a time makes contact, and the other is always "open" whenever the opposite one is closed. Just take a look at the wiring diagram - the GM wiring diagram doesn't care what the other people in this post have a "censensus" about - there is a big, 1/2-page diagram of the ignition switch contacts and contact positions in the Service Manual. Can you help me with this diagram? I don't seem to have a similar drawing in my '69 Service manual. The year manual that is interesting is the 1972 manual, which actually shows the two different switches (points ignition versus unitized ignition) and their contact positions. The pre-72 Manuals only show the points type switch with the separated IGN1 and IGN2, and the 1974+ manuals only show the HEI type switch with the bridged contact points. Fact is fact. I'm not arguing facts. I'm an engineer. I'm only interested in facts. I'm just trying to find a drawing of the mechanical and electrical workings of the switch. The way I'm understanding things, this is a poor way to design an ignition switch. The ignition switch was revised with the advent of the Unitized ignition, and the Unitized switch was subsequently used on HEI. On this revised switch, the IGN1 and IGN2 individual terminals were bridged together, and the wire to the "R" terminal on the starter was eliminated. This switch operates the way you're thinking the switch should operate, but that's not the case with a "real" pre-HEI ignition switch.
Lars

Yeah, I guess I just need to take a look at the actual switch drawing. IGN2 function still doesn't make sense to me, unless it's a misnamed Cranking/starter energizing output, unrelated to actual ignition. Can you steer me to a place to get this switch drawing you referenced?
Thanks,
Mike
 
I have the referenced schematics in my various years Service Manuals at the workshop. I'm at my office right now without access to the manuals, so what I can do is bring the manuals with me to the office on Tuesday (I don't have a fax in the workshop) and fax you the various info from the different years - there's even a written description on how the system works, and I think you'll find it interesting. Drop me an e-mail with your fax number and I'll get the info to you - send the fax info to both my workshop and office so I don't space it out:

[email protected]
[email protected]

Lars
 
Lars,

I don't have a fax here, but I do appreciate your offer. I'll just do some internet searching for that information.
Like I mentioned earlier, it's not an issue with my car, but the engineering design aspect of this switch is what's driving my curiosity.
 
Ignition Switch

Mike, I have a 79 factory manual that has an ignition circuit operation section. I could scan if you think it is usefull.
 
Mike -
I doubt you're going to find the complete text from the factory literature on the Internet - I have this stuff because I was an instructor for GM at the Training Center, and I kept all my original Delco factory training materials. This is original stuff from the early 70's - before Al Gore invented the Internet.

Here are excerpt quotes from the GM training literature on the switch operation. These are the real GM/Delco engineering documents, typed exactly as they are printed including the CAPITAL letters, but I have added the bold for empasis):

"...In the RUN position, the ignition primary circuit is activated through the resistance wire and the air conditioning, heater and defroster circuits are activated...

"...When the ignition switch is turned to the START position, the ignition primary circuit is activated directly, by-passing the resistance wire, and the starting motor is activated to crank the engine."

I'd say that's pretty crystal clear... I didn't make that up.

I have an entire page of description of ignition switch operation, plus the diagrams of the switch operation in all 5 modes of operation. This info is not contained on the chassis wiring diagram, so BBShark will not have this info unless he attended GM Training Center Courses on electrical systems. Further, the '79 system description that BBShark has is for HEI, and will not contain the unique separate systems for "RUN" and "START" used with the points systems cars prior to 1975. I'll be glad to fax you copies of this original GM literture if you want it.

Lars
 
No, I never attended GM training. Just trying to help.

Mike, my offer still stands.
 
BB-
I'm not slamming you - really. I'm just pointing out that your 79 service manual info will not contain the pre-75 dual-circuit info that Mike was trying to get info about. Many people think that all the C3 wiring stuff is pretty much the same (as witnessed by the "consensus" voting on how it must operate, earlier in this post), but there was a big change when GM went to HEI, especially in the cranking/ignition circuit, which included a complete re-design of the ignition switch and its cranking operation. Most parts houses (including NAPA) now sell only the HEI type ignition switch, because you can use the HEI switch in both points and HEI cars. But you cannot use an original points ignition switch on an HEI car... The majority of our cars have probably had their switches changed by now, so if you "ohm" one out, it will likely show parallel circuits. But the original switches did not have parallel circuits.
Lars
 
Was there ever a unitized chevy distributor? Never seen one, just pontiac, that is if by unitized you mean everything contained in 1 unit like the HEI, so a points distributor with a coil in cap... is that what you mean?
 
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