Fuse Cavity 5

[Charger21]

Working on my 73 Charger. I have no power to fuse cavity 5 (5A for dash lights, gear shift light, etc). Before I start messing with old brittle wires on the bulkhead, does anyone have any idea if the power to all cavities comes via one feed or if they have separate supplies?

Thanks!

 

[miller]

Guessing it's about the same, year to year. That power feed should come from your light switch. Only gets power, once the switch is on. But, think you also have a dimmer switch, for the instrument lights, that's wired into that circuit.

 

[Nacho-RT74]

I will post the full explanation for some other members knowledgement on how the system work...you take what you need

3rd gens headlight switch gets:

2 inputs...
one direct from alt splice between amm and alt to feed JUST headlights
one from batt source fuse box side ( 20 amps fuse ) to feed parkings and dimmer source ( dash, gearshift )

aaand 3 outputs
one for headlights
one for parking lights
one for dimmered lights

HOWEVER

the dimmer source RUNS BACK once again to the fuse box before spreads out to the cluster and everything dimmer controlled, gearshift face, radio face, acc lights. This fuse is AS FAR I RECALL 3 or 5 amps one and is one of the top fuse box ones ( can't recall if left or right ) and is separated from the batt and acc buss bars on back of fuse box

IF you still got parking lights, same as glovebox light and some other, then the input is nice including fuse, but not the output to the dimming system... either the related fuse is bad ( blown, broken or bad contacts ) or the dimmer wheel is not working for whatever reason... it can be just cleaned if is that OR simply replace the full switch assembly.

which side of the fuse you checked? inner terminal or outer ? the power flows from inner to outer. If you checked the outer terminal it can be still blown inside even not visible ( hidden by the fuse caps ). Check the inner terminal for power. If doens't get the power on inner terminal, then the problem could come from dimmer wheel... or broken wire?

 

[Charger21]

Thanks Nacho-RT74. I checked both inner and outer on cavity 5 - no power on either side. Tried changing fuse (before I tested the cavity itself). It is a 5A and it is the top right cavity. Sounds like maybe I should investigate the dimmer. I have seen that is a common problem. I just didn't think about how the dimmer could affect gear shift light, heater switch light, etc. but it makes sense since all of those would likely dim?

And yes I have parking lights and glove box lights. Also I saw you said in another post your fuse box was getting hot and you cleaned the terminals. What did you use to clean them? I figure while I am at it that it wouldn't hurt (hope I don't Jinx myself) to clean them up.

 

[Nacho-RT74]

I used a dremmel metallic brush to clean it

yes, gearshift, radio face, heater control and acc switches are also dimmer sourced. Same source for everything

it is very tipical get the rehostat sulfated with a greenish stuff there... If is that, is just about clean it ( vinegar with a bit of salt... lemon juice should work ). But also rehostat can get contacts broken, or simply switch damaged inside, which feeds the dimmer wheel...

 

[mopar 3 B]

Time to get that wiring diagram out. Start with what doesn't work and head towards the battery. When you find what works you can solve the problem.