74 dart can’t get a spark
Oil light power requires key switch in run
Regular brake lights are always hot.
Headlights are always hot.
As always with testing. Make sure the battery is fully charged.
Basic Standard layout is like this.
(Not shown is the '74 seat belt interlock wiring.)
All the wires connected to the battery are always hot.
Q1 feeds the fuses that are always hot.
J1 feeds the key switch.
J2 wires are fed from the key switch run terminal.
J3 is the fed from the start terminal. J3 bypasses the ballast resistor because at start the system votlage is low (10-12 Volts instead of 14is hwhen the alternator is running).
Wires A come and go from the battery.
Wires R relate to AlteRnator
J1 feeds the key switch
J2 is hot key in Run
For the ignition to work.
Key in RUN there should be power throughout the J2 circuit. Measure at the ballast junction and firewall connector
Key in START there should be power at battery voltage in the J3 circuit. Battery voltage will be less than 12 Volts because of the starter's draw. Measure the votlage at th ebattery as well and you'll see this for yourself.
This may be helpful WRT interlock
https://www.forabodiesonly.com/mopar/threads/ignition-issues-on-74-dart-sport.518427/post-1973922161
None of us know how the radio was wired in. Factory radio is powered from the switched side of the fuse box.
Oil light power requires key switch in run
Regular brake lights are always hot.
The fusible link is the only thing close to a 'master fuse'
Dome light is always hot.
Headlights are always hot.
As always with testing. Make sure the battery is fully charged.
Basic Standard layout is like this.
(Not shown is the '74 seat belt interlock wiring.)
All the wires connected to the battery are always hot.
Q1 feeds the fuses that are always hot.
J1 feeds the key switch.
J2 wires are fed from the key switch run terminal.
J3 is the fed from the start terminal. J3 bypasses the ballast resistor because at start the system votlage is low (10-12 Volts instead of 14is hwhen the alternator is running).
Wires A come and go from the battery.
Wires R relate to AlteRnator
J1 feeds the key switch
J2 is hot key in Run
For the ignition to work.
Key in RUN there should be power throughout the J2 circuit. Measure at the ballast junction and firewall connector
Key in START there should be power at battery voltage in the J3 circuit. Battery voltage will be less than 12 Volts because of the starter's draw. Measure the votlage at th ebattery as well and you'll see this for yourself.
This may be helpful WRT interlock
https://www.forabodiesonly.com/mopar/threads/ignition-issues-on-74-dart-sport.518427/post-1973922161
