Questions on wiring Ignition/ supplying power to the fuse box

[Kevo]

Hello everyone,

I have been redoing the wiring in my 1968 Dodge dart and had a bunch of questions. I bought an EZ wiring harness kit because the harness in the car now was incomplete. The previous owner has wired in their own ignition switches to bypass the keys, and had done a few other things that left quite a few cut wires.

My big question is how to hook up the ignition:
To be able to start the car with a stock ignition switch, how would I need to draw the power through the relay into the harness to use the ignition wire in the new harness? I have an alternator power line and a solenoid power line on the new harness, but nothing that seems to hook to the battery directly. The alternator power goes to the new fuse block, so currently the power that use to run from the alternator into the cab via the black wire in the second picture now goes nowhere, and I am not sure if I need to splice it into the new harness ignition wire to get power (It powers accessories and lights via the light switch, i planned to wire all of these with the new harness wires).

The previous wiring had direct power going to the ignition switch which would make the connection to the solenoid, in the wiring diagram im looking at, it seems this is normally drawn from the alternator via the black wire in the harness below.

The new ignition switch has the power coming in from the new wiring harness (red wire), this is where I was thinking I needed to add in the connection from the battery terminal on the ignition relay - unless the harness is getting power from somewhere else.

From there, I planned on piggy-backing off of the direct ignition wiring (red wire above) to power the light switch below via the Black TR (black with white line) wire.

Does this make sense? I feel like the wiring harness and diagrams show the power being drawn from the alternator for everything except the starter, but I am not sure how to connect all of the new wiring with the old wiring when it is all spliced together.

Thanks for your time

 

[67Dart273]

I don't know how this every worked and it seems labled wrong Originally, one large red came to the stud from the battery, and the other went through the bulkhead connector with a fuse link in series. Originally this went to the ammeter, and after passing through the ammeter the black on the other side of the meter became the main master power feed for the interior of the car. That went to a splice which fed the ignition switch, the fuse panel "hot" buss, the headlight switch (headlights only) and branched off (black) back through the bulkhead and to the alternator.

The "middle cyan" on the "square" terminal should go to the starter solenoid

One of the bottom ones gets grounded through the transmission neutral safety switch, and the remaining one gets the "start" signal from the ignition switch

 

[67Dart273]

If you are using a new harness, some of that should go through the new fuse panel in the new harness. And it would be a good idea to feed it from a relay to relieve the ignition switch

68 ignition switch:

Top left wire J1-12R. This is the main power INTO the switch. Originally this came from the big welded splice in the black ammeter wire under the dash. NOT FUSED!!

Middle left, J2-16DBL. This is IGN1 or "ignition run." It GOES DEAD during start, and supplies underhood ignition, voltage regulator and originally some smog doo dads on some models It also powers the cluster, such as gauges and brake warning lamp

Bottom........J3-14BR. Brown, this is IGN2 and feeds the coil power during start because as noted above, IGN1 goes dead during start. This is NOT connected to the solenoid and is a separate circuit

Middle right..........S2-18Y----this wire goes out through the bulkhead to one of the bottom two terminals on the starter relay. This is the START wire and activates the relay if the remaining relay terminal is grounded through the neutral safety switch

Bottom right........Q2-12BK. This is powered by the key in either ACC or "RUN." This feeds the ACC buss in the fuse panel

 

[67Dart273]

You need to download yourself a service manual from MyMopar and start in with it.


The yellows do not "power" anything. They are ground leg switching for the dome circuit. The yellows go to the door switch, and the terminal here on the light switch grounds when the knob is twisted to the left. Same thing as doors opening. Power goes to the insulated/ isolated lamp, back to the switches on yellows, and grounded to activate

Tan does NOT connect to turn indicators. It is part of the cluster illumination lamps from the dimmer control in the light switch. HOW THAT WORKS. The cluster lamps get power FROM the tail light circuit in the headlamp switch. When park or head is on, and when the dimmer control is rotated "somewhat left" power is supplied OUT of the tan wire, THEN (originally) down to the fuse panel to the INST fuse and then from that fuse, out on orange wires to all dimmer controlled lighting.

 

[67Dart273]

Light switch:

Switch terminal P.............wire .........L6-18Y is the park lights

switch terminal D is the yellow switch terminal for the dome lamps

switch terminal H feeds off to the dimmer switch and to the headlamps

switch terminal R is power to the tail and on later models, marker lamps. You can move the park lamps wire to this terminal if you want the park lamps to stay on with headlights

switch terminal B1, wire L1-16BK is the power into the switch ONLY for the headlamps, and originally came direct from the splice in the black ammeter wire. This wire WAS NOT fused originally

switch terminal B2 is fused and powers tail, park, and dimmer controlled dash lamps

 

[Kevo]

Light switch:
View attachment 1715672410

Switch terminal P.............wire .........L6-18Y is the park lights

switch terminal D is the yellow switch terminal for the dome lamps

switch terminal H feeds off to the dimmer switch and to the headlamps

switch terminal R is power to the tail and on later models, marker lamps. You can move the park lamps wire to this terminal if you want the park lamps to stay on with headlights

switch terminal B1, wire L1-16BK is the power into the switch ONLY for the headlamps, and originally came direct from the splice in the black ammeter wire. This wire WAS NOT fused originally

switch terminal B2 is fused and powers tail, park, and dimmer controlled dash lamps

View attachment 1715672400

If you are using a new harness, some of that should go through the new fuse panel in the new harness. And it would be a good idea to feed it from a relay to relieve the ignition switch

68 ignition switch:

Top left wire J1-12R. This is the main power INTO the switch. Originally this came from the big welded splice in the black ammeter wire under the dash. NOT FUSED!!

Middle left, J2-16DBL. This is IGN1 or "ignition run." It GOES DEAD during start, and supplies underhood ignition, voltage regulator and originally some smog doo dads on some models It also powers the cluster, such as gauges and brake warning lamp

Bottom........J3-14BR. Brown, this is IGN2 and feeds the coil power during start because as noted above, IGN1 goes dead during start. This is NOT connected to the solenoid and is a separate circuit

Middle right..........S2-18Y----this wire goes out through the bulkhead to one of the bottom two terminals on the starter relay. This is the START wire and activates the relay if the remaining relay terminal is grounded through the neutral safety switch

Bottom right........Q2-12BK. This is powered by the key in either ACC or "RUN." This feeds the ACC buss in the fuse panel









View attachment 1715672412

So my main power into the switch is now from the new fuse block under the ign. wire. This has now broken the big welded splice as the fuse block connects to the alternator. I can now use the fuse block to power a lot of the accessories that were on the circuit, but at that point would the switch need power to that circuit anymore? The headlamps are already on the new circuit.

I will digest the rest of the information your provided, im sure i will have more questions, but this is a huge help already.

Thanks,

 

[67Dart273]

Not sure what you mean. Normally the IGN switch was supplied by a very large direct wire. You can put a large fuse/ breaker inline. I would REDUCE the load on the ignition switch by using the switch to fire a relay (or two) and use the relays then to feed the loads. I've no idea what your overall wiring will "be." For example, if you use a conventional alternator using a regulator with "sensing" (as opposed to a "one wire" alternator) ---part of the problem in these cars (or any other) is that overall voltage drop in the path from battery---through wiring, terminals, and switches---this results in reduced voltage to the VR--and that causes it to overcharge because it "thinks" the battery voltage is low

By using the key to fire a relay you can reduce or eliminate this problem These switches are old and nnot easy to find, and new replacements are low quality

 

[famous bob]

So my main power into the switch is now from the new fuse block under the ign. wire. This has now broken the big welded splice as the fuse block connects to the alternator. I can now use the fuse block to power a lot of the accessories that were on the circuit, but at that point would the switch need power to that circuit anymore? The headlamps are already on the new circuit.

I will digest the rest of the information your provided, im sure i will have more questions, but this is a huge help already.

Thanks,

Which E Z kit did u use ? I used a 12 circuit kit , and had none of the mentioned problems, looks like ur using a bunch of old wiring in the pics.
Call E Z and see if Sean is still there , he can walk u thru anything ! My biggest problem was w/ the ignition switch --------------jfi

 

[Kevo]

Not sure what you mean. Normally the IGN switch was supplied by a very large direct wire. You can put a large fuse/ breaker inline. I would REDUCE the load on the ignition switch by using the switch to fire a relay (or two) and use the relays then to feed the loads. I've no idea what your overall wiring will "be." For example, if you use a conventional alternator using a regulator with "sensing" (as opposed to a "one wire" alternator) ---part of the problem in these cars (or any other) is that overall voltage drop in the path from battery---through wiring, terminals, and switches---this results in reduced voltage to the VR--and that causes it to overcharge because it "thinks" the battery voltage is low

By using the key to fire a relay you can reduce or eliminate this problem These switches are old and nnot easy to find, and new replacements are low quality

Yeah its hard to explain when I am not sure exactly what I am doing. So the very large direct wire that fed the ignition switch was supplied from the alternator, this power is now going into the new wiring harness via the alternator power wire. I have the ignition wire from the new wiring harness hooked up to supply power to the ign switch. I traced the other wires from that direct wire back to that switch, but now that the headlights are on the new harness, I will hook them up in their place along with the marker lights/tail lights and leave any of the accessories off to be handled directly from the new wiring harness fuse black. Does this make sense/sound like the ideal route to take?

 

[67Dart273]

No it was not supplied by the alternator "exactly. Originally, because of the ammeter, and the need for it to be able to display current flow either from or to the battery (discharge vs charge) BOTH the battery an alternator wiring had to appear at the ammeter. It's all one wire. Here is an article about repairing bad bulkhead connections, but in this case what you are looking at is the simplified power distribution diagram.

Follow along in the diagram. This is a simplified diagram of pretty much original OEM. Bear in mind that the ammeter is basically a "piece of wire". So the RED wire shown starts out at the battery, goes to the starter relay "big stud" which is part of the relay contact, BUT ACTS AS A JUNCTION point. From there to the fuse link, then through the bulkhead connector an to the AMMETER, through it an out on the BLACK wire an to the WELDED SPLICE. This splice is up near the cluster a few inches from the ammeter. The BLACK continues on out through the bulkhead and to the alternator

LOOK AT the welded splice. This is simply a branch, tap, take off point. The battery and alternator ARE CONNECTED SIMPLY by the path just described.

The "WELDED SPLICE" taps off to the various points shown AND IS SUPPLIED by whichever is more positive........the battery....or the alternator. If the alternator is charging, and outputting more voltage than the battery, then the power comes from the alternator. If the alternator is not spinning fast enough, or the engine not running, then power comes from the battery.

Catalog

The big question for you is, "are you going to retain the ammeter" because if you are, it's a fair amount of extra wiring with LARGE wire (needs to be upgrade from OEM) an the ammeter itself can give trouble with high output alternators. Frankly I would eliminate it an replace it with a voltmeter

 

[Kevo]

No it was not supplied by the alternator "exactly. Originally, because of the ammeter, and the need for it to be able to display current flow either from or to the battery (discharge vs charge) BOTH the battery an alternator wiring had to appear at the ammeter. It's all one wire. Here is an article about repairing bad bulkhead connections, but in this case what you are looking at is the simplified power distribution diagram.

Follow along in the diagram. This is a simplified diagram of pretty much original OEM. Bear in mind that the ammeter is basically a "piece of wire". So the RED wire shown starts out at the battery, goes to the starter relay "big stud" which is part of the relay contact, BUT ACTS AS A JUNCTION point. From there to the fuse link, then through the bulkhead connector an to the AMMETER, through it an out on the BLACK wire an to the WELDED SPLICE. This splice is up near the cluster a few inches from the ammeter. The BLACK continues on out through the bulkhead and to the alternator

LOOK AT the welded splice. This is simply a branch, tap, take off point. The battery and alternator ARE CONNECTED SIMPLY by the path just described.

The "WELDED SPLICE" taps off to the various points shown AND IS SUPPLIED by whichever is more positive........the battery....or the alternator. If the alternator is charging, and outputting more voltage than the battery, then the power comes from the alternator. If the alternator is not spinning fast enough, or the engine not running, then power comes from the battery.

Catalog

View attachment 1715672918

The big question for you is, "are you going to retain the ammeter" because if you are, it's a fair amount of extra wiring with LARGE wire (needs to be upgrade from OEM) an the ammeter itself can give trouble with high output alternators. Frankly I would eliminate it an replace it with a voltmeter

This diagram is a huge help. I can delete the ammeter easily, and easily hook in a voltage meter, but I am not sure how I should be doing this to route it through the new wiring harness/fuse box. Right now the alternator is connected to the new fuse box, and this circuit is cut at the alternator. I had planned to run the ignition, lights, dome light, etc through the new harness as it has independent wires for each and hook them into the existing switch, but seeing as how it is all connected I wanted to plan out the circuits before I started wiring them together.

So if I run the ignition switch power wire from the new harness to J1-12R, run the ignition switch coil wire to J3-14BR (and hook other side through ballast resistor to coil) , run ignition switch start to S2-18Y and connect it to the relay, and run J2-16DBL to the needed items in the dash (tail lamps covered by another circuit now) - do you think that would work? I could put the voltage meter on the ignition switch power in this case.

Let me know what you think

 

[67Dart273]

What we need at this point is a link to the manual with your wiring kit Some of that should be documented in that manual.

To "demistify" (I hope) the ignition switch, here is what you have going into and out of

MAIN POWER IN This originally came off the "welded splice" and was NOT fused.
"IGN1" ignition run.......this powers the cluster, warning lamps, ignition system, VR and alternator field, and smog devices and electric choke if used

"IGN2" This powers ignition system ONLY in "start" because IGN1 goes dead in "start."

ACC This feeds out to the ACC fuse buss in the fuse panel and feeds radio, heater, wipers, etc It is of course "hot" both in "run" and ACC

START....This is normally yellow an goes to one of the coil terminals on the start relay.