@nodemon has the shop manual and the diagrams. Its a matter of helping him read it, and how to then use it.
See june '68 here
[URL]https://www.web.imperialclub.info/Repair/Lit/Master/index.htm[/URL]
or
[URL]https://mymopar.com/chrysler-master-tech-service-library-browse-model-year/[/URL]
A short is when the circuit connects in some way that allows electicity to flow but shortcuts whatever it is we wanted to power.
A bad ground, the circuit can not complete and so electricity doesn't flow.
The ammeter show current (amount of electricity moving) in or out of the battery. So that's helpful to observe.,
So the the heater and wipers are fed from the switched accessory circuit. So power is making it to the key switch and out.
Headlights get a dedicated feed but does tell you that the battey feed to main distribution point (a welded splice) is good.
Tailights, and brake lights are on fuses that are always hot.
Dashlights are on a circuit that branches off inside the headlight switch. This one is a good place to start diagnosing.
The other guys have started to help with this - which seems to be some sort of cross wiring related to the instrument cluster.\
The meter can show Voltage, and continuity as well as resistance between any two points.
However - When the battery is connected use voltage (DC). Usually one probe will be on the ground, o negative and the other on the point you expect to be at battery voltage. Even when the engine is running from power coming from the alternator, people say 'battery voltage'. But in this case, we are talking battery voltage. Get familiar with it. Go over to the battery and measure the voltage across it. Then measure the voltage at the big junction on the starter relay, and then at the alternator output terminal. They are all connected and should al;l be at the same voltage.
When the battery is disconnected, then use the continuity and resistance (ohms) settings.
For your first diagnoses, turn on the parking lights, turn the instrument lights to mid or high and measure voltage on both sides of the instrument lamp fuse. If there is voltage on both sides, then the problem is downstream.
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