Searching for 12v switched power after ditching ballast and installing aftermarket electronic ignition

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Im trying to locate a proper wiring diagram for the ignition switch for 1977 as I only have one for 1976, and I know the ignition switch and starter relay changed in 1977. The reason it may SEEM I am overcomplicating this is because IGN1 (the blue wire) is ran just as mentioned here, and also as per my wiring diagram for 1976 (and I imagine into the later years as well). IGN 2 however is not something I have been able to locate, atleast according to the help here and my 1976 manual- The brown wire itself that even in the 1976 diagram is shown going right from the switch to the ballast, actually does not exist on the 1977 harness...Instead, the brown wires that are joined going to the 0.5OHMS side of the ballast split to the positive side of the coil (as it should per diagram) and the other traces back to the "BAL" side of the starter relay...Hence, this is why I am trying to find a 1977 schematic (so far with no luck) as I am wondering if in 77 the yellow ignition wire energizes the starter relay at "I" and then powers the brown wire at "BAL" which travels to the ballast resistor and joins the coil wire. IF that is the case, then I can join the IGN1 blue wire to this brown wire, but if not, I am pi$$ing in the wind.

Below is a picture from my 1976 electrical service manual, but on my harness, ignition 2 does not do a straight run to the ballast, hence why I am trying to find a schematic for the starter circuit for 1977
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he bypass circuit SHOULD NOT feed from the start circuit. That is because, when in "park" or "neutral" on on a stick car, when depressing the clutch, (grounding the start relay) the coil cicuit of the "start" relay is being backfed/ powered by the coil end of the ballast resistor. This not only puts a load on the ballast and reduces coil power, but in some cases with a "sensitive" start relay, this backfeed MIGHT actually engage the starter!!

That is exactly why in my previous post I spoke of ways to imitate the bypass circuit--with another relay, with the newer Jeep starter relay, or with a series diode off the "start" line.



You can actually make a table of the ignition switch yourself easily. Do not get too hung on colors as they may have changed. There is only so much that can possibly come and go from the switch.

1...Turn the switch to ACC. Probe the switch wires and determine what is continuous. A will be feed from the battery and B will be source for accessories.

Even if this is a "mystery" switch, it's easy

2...Next you have to differentiate between A and B. Which is the batt and which is the ACC, you have two colors now identified, but which is which.


Take A, and probe all of the others while holding the switch to "start." If no result, then A is "accessory." Double check by connecting "B" to the meter and re probe. There will be one or two that connect with B. So, B whatever color, is the batt feed, the other two are the start and the bypass.

3...Set switch to "run." If correct, B will now be again continuous with "A" "accessory" and also continous with the "run" wire.

4.... Last, which one of the two you ID'd in the "start" test are actually "start" and "bypass?" The fact is it does not matter. Both are ONLY continuous in "start" and they feed from separate, isolated contacts.

Any smaller wires coming from the connector are such things as horn (small black) column mount shift quadrant, "key in" lighting or "key in" activated switch, etc.
 
It seems IGN 2 begins at the starter relay. This is similar to how starter solenoids were set up on Jeeps to later 1980. When the relay trips, the ignition feed is connected to the power at the relay. When the key is released from start to run, the regular ignition feed connect to power through the key switch.
 
Bishko has been a big retailer of new and used service manuals etc. Try them.
 
What I'm saying is that it sounds like the start wire from the igntion switch controls the relay
When the relay closes, power goes from the battery feed on the relay to the starter solenoid and to the ignition start wire.
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Up through '76 for A-bodies, the relay does not have the BAL terminal. The EGR was connected to the SOL terminal so functionally that's the same.
 
Diagram here. J3 come sfrom starter relay

Ballast resistor wiring

I'm curious to see other vehicles wiring at the ballast resistor. I swapped my blue wires to match the wiring diagram (the picture was taken afterwards). The small blue jumper wire was hooked to the side with the big brown wire. I'm sure it's not a significant difference but I'd be curious...
www.forfmjbodiesonly.com
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67Dart273 said:
he bypass circuit SHOULD NOT feed from the start circuit. That is because, when in "park" or "neutral" on on a stick car, when depressing the clutch, (grounding the start relay) the coil cicuit of the "start" relay is being backfed/ powered by the coil end of the ballast resistor. This not only puts a load on the ballast and reduces coil power, but in some cases with a "sensitive" start relay, this backfeed MIGHT actually engage the starter!!

That is exactly why in my previous post I spoke of ways to imitate the bypass circuit--with another relay, with the newer Jeep starter relay, or with a series diode off the "start" line.



You can actually make a table of the ignition switch yourself easily. Do not get too hung on colors as they may have changed. There is only so much that can possibly come and go from the switch.

1...Turn the switch to ACC. Probe the switch wires and determine what is continuous. A will be feed from the battery and B will be source for accessories.

Even if this is a "mystery" switch, it's easy

2...Next you have to differentiate between A and B. Which is the batt and which is the ACC, you have two colors now identified, but which is which.


Take A, and probe all of the others while holding the switch to "start." If no result, then A is "accessory." Double check by connecting "B" to the meter and re probe. There will be one or two that connect with B. So, B whatever color, is the batt feed, the other two are the start and the bypass.

3...Set switch to "run." If correct, B will now be again continuous with "A" "accessory" and also continous with the "run" wire.

4.... Last, which one of the two you ID'd in the "start" test are actually "start" and "bypass?" The fact is it does not matter. Both are ONLY continuous in "start" and they feed from separate, isolated contacts.

Any smaller wires coming from the connector are such things as horn (small black) column mount shift quadrant, "key in" lighting or "key in" activated switch, etc.
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All I know is that the car was running with the wiring this way. I only took out the harness to go through it, and figure out finding switched 12v power. Those tests I could definitely run once I get the harness and battery back in the car, as well as the engine/trans (hopefully this weekend)
Mattax said:
It seems IGN 2 begins at the starter relay. This is similar to how starter solenoids were set up on Jeeps to later 1980. When the relay trips, the ignition feed is connected to the power at the relay. When the key is released from start to run, the regular ignition feed connect to power through the key switch.
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That's how it appears, but without the manual its a guess
Mattax said:
Bishko has been a big retailer of new and used service manuals etc. Try them.
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I just ordered this 76 electrical manual off ebay because it was local and I thought, hell 77 and 76 must be practically the same...DOHHH lol
Mattax said:
What I'm saying is that it sounds like the start wire from the igntion switch controls the relay
When the relay closes, power goes from the battery feed on the relay to the starter solenoid and to the ignition start wire.
View attachment 1716258847


View attachment 1716258848 Up through '76 for A-bodies, the relay does not have the BAL terminal. The EGR was connected to the SOL terminal so functionally that's the same.
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Yes, I am very aware that 76 and 77 had difference starter relays, hence why I thought maybe the relay could start IGN2 circuit
Mattax said:
Diagram here. J3 come sfrom starter relay
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View attachment 1716258854
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Damn man, I searched high and low for a 77 diagram like this, and you found one! Thank you! So J3 as I have been saying on my 77 starts at the starter relay....Now I wish I had the diagram it mentions on page 5 of that manual.

Based on this image though, can I connect J3 (brown wire coming from starter relay) to J2 (Blue wire on other side of ballast coming directly from the ignition switch) and get the effect I am after- a switched 12v, both in run and start, to supply a small power source (My little fuse block)?
 
Depends on what is runningoff of that fuse block. The wire is 14 ga SAE, but when running goes though a bunch of connections and the start switch. Not sure but probably not fused - which is both good and bad. Less resistance is good. No protection for non-engine items on the engine circuit is bad. There's probably a fusible link on the feed. if so probably two sizes down from 14, which would be 18 ga. A CD ignition box like an MSD pulls very little current for its internal relay so that's why I felt confident saying hook it up even with the 1/2 ohm resistor in place. But if its running electric fans, fuel pumps, etc, then got to add up the amp flowing through those wires and fuses at running voltage (14.5 V). Add that to the field current draw, turn signals, wipers, and anything else that could be on at the same time using that same feed fusible link (to J1) and the branch (J2). Wires in the engine compartment will get hot so have reduced capacity.
 
Mattax said:
Depends on what is runningoff of that fuse block. The wire is 14 ga SAE, but when running goes though a bunch of connections and the start switch. Not sure but probably not fused - which is both good and bad. Less resistance is good. No protection for non-engine items on the engine circuit is bad. There's probably a fusible link on the feed. if so probably two sizes down from 14, which would be 18 ga. A CD ignition box like an MSD pulls very little current for its internal relay so that's why I felt confident saying hook it up even with the 1/2 ohm resistor in place. But if its running electric fans, fuel pumps, etc, then got to add up the amp flowing through those wires and fuses at running voltage (14.5 V). Add that to the field current draw, turn signals, wipers, and anything else that could be on at the same time using that same feed fusible link (to J1) and the branch (J2). Wires in the engine compartment will get hot so have reduced capacity.
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The fuse block is currently going to run the Mallory CD ignition, an Autometer tachometer, and a basic CD deck....at some point later down the road, it may get an electric fuel pump, which is something that may be added to this fuse block, so setting up the wiring now for future growth makes the most sense for me.

Probably a silly question, but I am very green in the wiring department- Does the fact that J2 and J3 are going to a relay, before powering my auxiliary fuse block, make the scenario any better? Again, I am probably going to go overkill on the relay purposely for future growth.

Thanks for all the back and forth and assistance, it truly is appreciated!
 
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Just found electrical service manuals completely separate book from chassis service manual. 1976 all mopdels except valiant and dart had something called field-loads relay. One year only, trouble diagnosing if you did not know what it was or what it did or where it was. Relay controlled power to heater fan switch and alternator field circuit. Going to start separete thread about this as might be good reference material for future use.
 
Bugman said:
Just found electrical service manuals completely separate book from chassis service manual. 1976 all mopdels except valiant and dart had something called field-loads relay. One year only, trouble diagnosing if you did not know what it was or what it did or where it was. Relay controlled power to heater fan switch and alternator field circuit. Going to start separete thread about this as might be good reference material for future use.
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Yes, not sure what year, they went from being 1 manual to separate for chassis and electrical.

I have a 1977 chassis manual, and a 1976 electrical. Being my car is a 77, I really thought there wouldn't be much difference in the electrical components throughout the years of the same vehicles, but clearly I was wrong.
 
mshred said:
The fuse block is currently going to run the Mallory CD ignition, an Autometer tachometer, and a basic CD deck....at some point later down the road, it may get an electric fuel pump, which is something that may be added to this fuse block, so setting up the wiring now for future growth makes the most sense for me.

Probably a silly question, but I am very green in the wiring department- Does the fact that J2 and J3 are going to a relay, before powering my auxiliary fuse block, make the scenario any better? Again, I am probably going to go overkill on the relay purposely for future growth.

Thanks for all the back and forth and assistance, it truly is appreciated!
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I don't really understand what you mean with J2 and J3 going to a relay. Draw a diagram.

Not sure why you need a fuse block for the ignition on wire, or a tach. CD deck I would power from the auxilery buss if there is room in the OEM fusebox. Alternately have it trigger a better connection using a relay and fuse. It doesn't need to be on during start and the battery is already under lots of load.
With an electric fuel pump, yes it will be best to be on during run and start. How much current it draws at 12 and 14.5 V will determine if the wiring is sufficient. There's really no reason to use one with a carb. EFI is another story.
 
Mattax said:
I don't really understand what you mean with J2 and J3 going to a relay. Draw a diagram.

Not sure why you need a fuse block for the ignition on wire, or a tach. CD deck I would power from the auxilery buss if there is room in the OEM fusebox. Alternately have it trigger a better connection using a relay and fuse. It doesn't need to be on during start and the battery is already under lots of load.
With an electric fuel pump, yes it will be best to be on during run and start. How much current it draws at 12 and 14.5 V will determine if the wiring is sufficient. There's really no reason to use one with a carb. EFI is another story.
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The joining of blue and brown mentioned earlier in this thread to create 12v switched power, that joint, is going to be the feed for a relay that sends power to this aux fuse block. But the more I think about it, I guess that relay is not a replacement for a fusible link or fuse. Also, im the last guy who could draw a diagram for this lol.

And technically, I dont need it. But I want these added accessories to be in one place, clean, and easy to access....I cant stand crawling under a dash, and I also want something that can allow future growth for any additional circuits in the future.

Many reasons to use an electric pump with a carb, but thats not important right now.
 
Are you using a scanner? Sometimes setting for grayscale works better.
Alternatively, if you make it a pdf file, althoug it won't post as an image people can open it and read it at full size.
 
That J3 14 BR ,suggest you test that connection for back feed. From blow up of relay inside wiring appears to not be connected to any thing else. To be sure put 12 volts on J3 and then see if voltage shows up on other relay connections
 
Yes using scanner,will try grayscale. Thank you for that info. Will look at pdf option.
 
Bugman said:
That J3 14 BR ,suggest you test that connection for back feed. From blow up of relay inside wiring appears to not be connected to any thing else. To be sure put 12 volts on J3 and then see if voltage shows up on other relay connections
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I read it the same way. Key in any position otehr than start and J3 is isolated from the other relay terminals.
Key in start, power from ignition switch through the safety switch (S2 to S4) causes the contacts to connect the battery feed to the J3 (lower contact). The upper contacts send power to the starter solenoid.
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Don't know if you are beyond this yet?

I had good luck using this Volt Meter to see charging voltage, when I did the 1 wire Alternator conversion on the '89 truck.

Simple 12 volt wire hookup, the other spade on the back goes to ground.

Works surprisingly well.

Screenshot_20240609-082536_Gallery.jpg



☆☆☆☆☆
 
Mattax said:
I read it the same way. Key in any position otehr than start and J3 is isolated from the other relay terminals.
Key in start, power from ignition switch through the safety switch (S2 to S4) causes the contacts to connect the battery feed to the J3 (lower contact). The upper contacts send power to the starter solenoid.
View attachment 1716259453
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So, in 75 Mopar had FOUR brown wires connecting to the relay??? No wonder you poor guys can't figure this out.
 
'77 F-body
OP was thinking the '76 diagrams would get him through.

Yes 4 brown, but all different enough. The confusion began with why there was no J3 at the ignition switch. Answer because they power at from the relay.
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Hey gents,

Sorry for the late reply. Had a busy weekend getting the engine and trans back into the car that is being discussed here, as both were out for rebuild over the winter. The plan this week is to get the harness back into the car and run some tests with the volt meter to see where I can pull power from to do what I am after here. I have not delved into it yet, but I also upgraded to a newer style mini starter, so that might add some more wiring changes for me as well.

I am very green with all wiring stuff, so what may seem easy or common sense to some, its like the early stages of learning Japanese for me.
 
How it Works:
Use your finger on the citrcuit diagram to follow the path. Keep in mind the path does not end at the device. To be complete it goes back to the power source.

Current is electrons moving. No movement = no current, therefore zero amperes.

Voltage is an measure of electrons excited, looking to go somewhere. Voltage indicates potential energy available at that location being measured. It is a relative measurement. If the second lead is on ground, then its voltage above ground. If the second lead is another location in the circuit, then its a voltage difference between those two points.
Example
Imagine the engine is off. Turn on the headlights. The electrons flow through the headlight switch, and through to the headlights and then return to the battery negative. Ideally voltage stays the same all the way up to the headlight filament.

With nothing running a voltmeter only reveals where there is potential. It does not show whether the circuit leading to it can handle a load. A load causes flow when there is potential difference. More voltage results in higher flow. But when there is a small wire, or poor connections, these cause resistance to increasing flow.

When there is no flow, the voltage will be the same everywhere. So with everything off, the alternator stud, battery positive and all the wires in between should be at the same voltage (even if there are bad connections).


Analogy
Its just like pressure. If there is 12.8 psi on one end of a closed pipe, its 12.8 psi throught the pipe.It doesn't matter if inside the pipe there is a partial blockage. It's still 12.8 psi throughout.
If we could look inside, the pressure on both sides of the blockage would be 12.8.

upload_2019-5-14_17-36-39.png



Connecting that same pipe to an air gun or an impact wrench and lets see what happens to the pressure.
There's still 12.8 psi supplied, but on the other side of the restriction the pressure is lower. The more air being used downstream, the more the pressure drops.

upload_2019-5-14_18-9-56.png




So now you can study the wiring and circuit diagrams. Use your finger to follow the path from the alternator (power supply) to the various components.
Keep in mind the battery is special. When its charged, it draws no current. After starting, it needs recharge. The more it has been discharged, the more current it will initially draw upon recharge. An advantage of the '75 up wiring is the battery's needs are split off from the key switched circuits on the engine side of the firewall. But it does add more fusible links. Each of those can become restrictions if too much current is going through them.
 
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