Fuse block

[Zedducus]

Installed new harnesses on my 72 charger 318.
Only one I did not change was the steering column, my problem is the following on my fuse block the Accessories fuse has no power with the key on or off
When I try to start my car it does now , but only if I hold the key down As soon as I let go of the key it turns off. Would this have anything to do with it?
If not what can I do to keep my car running and idling?

 

[Rockland71GTX]

It sounds like the starter wire is connected to the accessory circuit. Go to https://mymopar.com/service-manuals/
You can download a service manual there that has the wiring diagrams to trace out the circuits

 

[Budnicks]

welcome

 

[moes]

could be the switch or the wiring at the bulkhead connector. Check both sides of the ballast resister with a VOM and the key on.
I would next check the connectors under the dash for voltage with the key on. Does the radio, turn signals work when in the run position. If you have voltage at the switch check both sides of the bulkhead connector.

 

[69 Sleeper Bee]

Welcome from North Florida.
Lets see some pictures of the Charger.

 

[Zedducus]

Welcome from North Florida.
Lets see some pictures of the Charger.

 

[Zedducus]

It sounds like the starter wire is connected to the accessory circuit. Go to https://mymopar.com/service-manuals/
You can download a service manual there that has the wiring diagrams to trace out the circuits

Thanks

 

[Zedducus]

could be the switch or the wiring at the bulkhead connector. Check both sides of the ballast resister with a VOM and the key on.
I would next check the connectors under the dash for voltage with the key on. Does the radio, turn signals work when in the run position. If you have voltage at the switch check both sides of the bulkhead connector.

I’m thinking that’s what’s going on all my other fuses have power

 

[69 Sleeper Bee]

Looks like you are headed in the right direction
Good luck finding out your wiring issue.
Looks like you already got some good suggestions of what to try next.

 

[Zedducus]

Looks like you are headed in the right direction
Good luck finding out your wiring issue.
Looks like you already got some good suggestions of what to try next.

Thank you

 

[dan juhasz]

ballast resistor issue?

 

[polywideblock]

g'day from Australia

 

[Nacho-RT74]

it sounds as an ignition switch failure

Cabin power has nothing to do with engine bay power. If you are getting problems on both, is not likelly a firewall conector issue but an ignition switch issue... check the plug itself!!! Maybe could be just the connection and not the ign switch itself

With key RUN you should have power on:

Ign1 circuit which is blue wire on ign switch harness:
-Brake light on cluster ( if emergency brake is applied ) and oil light if standard cluster.
-ballast circuit ( blue side ), regulator blue wire, alt field blue wire and one of the ECU pins ( if elec ign )
-Coil brown wire... if ballast is good. Not full 12 volts but 5-9 volts

Acc circuit which is black wire on ign switch harness:
-Of course all the Acc side of fuse box, being able to turn on radio, apply turning lights, turn on wipers...

While cranking ( START )... brown wire on ign switch harness
-full 12 volts at coil
-dimmered power on the rest of the Ign1 circuit ( 5-9 volts ) as far ballast is good. You should be able to see the brake light on cluster dimmering out while cranking.
-No power at all on any ACC

also
-yellow wire from ign switch up to starter relay

knowing that you should be able to track down where is the fail

 

[Hey-O]

Welcome from Missouri!!