instrument lighting fuse(1969)

[roger01]

im trying to get my dash lights to work as they were  working before ...now they are not...everything else is working ....i have found that when i try to turn the dash lights brighter.....it doesnt ...when i click it to turn the dome light on..... the fuse blows ....what could be causing this ....everything else works ,even with the fuse blown ....are the dash lights the only thing on that fuse ....also does anyone know what color the wire for the instrument lights is ..at the fuse box ?....thanks

[Just 6T9 CHGR]

Most likely a short at the dimmer switch....fairly common problem with age.

Take out the switch & clean the contact wheel of corrosion

[roger01]

you think i can take it out without removing the dash cluster.......please say yes ..... 

[Ghoste]

I think it has to come out.  Unless you're really up your contortionist skills.

[roger01]

how is it in is it screwed or clipped anyone have a pic of the back of the dash

[Ghoste]

Well, the shop manual describes it like this;
1. Remove instrument cluster.
2. Disconnect wiring connector.
3. Disconnect heater vacuum hoses for accessibility.
4. Remove two switch mounting screws.


You know, I thought there was a pic of the back of the cluster in there someplace but I can't seem to find one.

[roger01]

sorry i didnt mean the dash.... done that too many times ,,,,,,,i meant the dimmer switch....
    and again is that the only thing on that fuse ....and what color is the wire if anyone knows ....thanks

[TylerCharger69]

Well....it's probably the dimmer switch, however...you say when you click it up to turn on the dome light...the fuse blows.   You could have a short in that wiring going to the dome light too.....does the fuse blow  when the doors are opened??

[roger01]

no ...only when i click it all up ....thats why i wanted to know what the color of wire was at the panal....

[Just 6T9 CHGR]

It can be removed while the dash is in the car.....I have done it......not easy though

Its held in there by 2 phillips screws to the right of the body of the switch

Heres a pic

[roger01]

boy....youve got a pic for every ocassion...now from what i see from the pic , the wires are 2 yellow ones and  a brown and a green
   so when i roll it all the way up when it clicks it blows the fuse..... but the dome lights still stay on ....so which wire would be the calprit ..
keepin in mind that when im rolling the dash lights up they are not on ...even when i put in a fresh fuse ...they are not on ......
      you guys still think its the switch it self or should i start hunting through these wires

[69CoronetRT]

   so when i roll it all the way up when it clicks it blows the fuse..... but the dome lights still stay on ....so which wire would be the calprit ..
keepin in mind that when im rolling the dash lights up they are not on ...even when i put in a fresh fuse ...they are not on ......
      you guys still think its the switch it self or should i start hunting through these wires

Sounds like you are describing a bad switch. Here's what mine looked like when I took it out. The coil was broken. Yours could be broken too and binding up to the point that when you roll it up to ground the courtesy lights, it's shorting out.

[69CoronetRT]

   so when i roll it all the way up when it clicks it blows the fuse..... but the dome lights still stay on ...

The dome/courtesy lights are a separate circuit and on a different fuse. Once you get the switch out, you can see the top lug is the portion that grounds the dome light to the case completing the circuit.

I can supply a schematic from the FSM if you need one but switches are often the culprit. Here's the bad news...none are available in the aftermarket. Ebay, salvage or good friends only. DAMHIK.

[roger01]

not available .....that sucks ,i guess im driving with no dash lights for a while ....

[JimShine]

If the problem is in the switch, why not bypass the dash light section of the switch until you find a new one? Your lights will be full brightness and non-adjustable, but is that a bad thing?

[mopar1968]

If the problem is in the switch, why not bypass the dash light section of the switch until you find a new one? Your lights will be full brightness and non-adjustable, but is that a bad thing?

I did exactly that.  Bypassed the dimmer switch (malfunctioning) and t-tapped into the parking light wire to connect to the dash light circuit.  This way dash lights work, and I can at my leisure find a new replacement dimmer switch.

Mine wasn't blowing fuses, but was not lighting up the dash lights all the way.  I left the dimmer circuit connected so as to be able to turn the dome light on and off.

Hope this helps a bit....

[roger01]

sounds good to me ...how do i by pass which wire where?

[mopar1968]

sounds good to me ...how do i by pass which wire where?

My dash is all put back together, but it's easy to do.  Using a DVOM or Test Light, find the parking light wire on the switch.  Then, make a temp wire using t-taps to jump to the dash light circuit (pink wires?).  That's it.

[roger01]

whats a t tap look like ...?

[mopar1968]

whats a t tap look like ...?

Well, they are similar to a scotch lock if you know what that is?  It is a device that clips onto a wire, and pierces it ever so slightly to make contact.  Then you make up a jumper with the correct crimp on connector, and it plugs into the t-tap.  That way you don't have to cut and splice your factory wire.  They are NOT for permanent repairs, but come in handy for testing and temp work like I did. 

Eventually I will replace my entire cluster with modern gauges, but until then the t-tap solution works.

[roger01]

is the key hole light afeected by the dimmer switch  ?.....i just realized mine stopped working ....

[Ghoste]

Does your courtesy light still work off of the door switch?

[roger01]

yes all  other courtesy lights work

[Ghoste]

Then I'd be more inclined to check that bulb first or the timer relay for it.

[roger01]

i took my dash out today ,just a couple of inches to change a bulb ....now as i rocked it a bit with the headlights on and no key in the ignition the dash lights came on ,....the dome light dimmed down  (door was open) ,....and the fuel guage went to full...any body have any ideas on to where to look for the problem .... i was having problem with my fuel guage  and dash lights could this be just a loose wire somewhere ?and where would it most likely be .........thanks

[hulter]

I am having the same problem on 68 charger with the gauges going to the right when the dimmer switch is pushed up to give more volts to the cluster lamps.  There are 2 power pins to the clluster and 3 sender pins from OP, temp and fuel senders.  The main supply power pin is 12v always and the other power pin is just for the lamps and gets its voltage off of the dimmer output which runs thru its own fuse in fuse panel as noted above.  If you get voltage bleeding (short) from lamp traces in cluster to gauges (they normally run on 5 volts due to resistor/limiter function), then in theory the gauges can get more voltage than normal and go to right.  When I turn up the dimmer, my 3 gauges go to right.

Does anyone know somebody who is set up to do bench testing of cluster with voltage to both power pins as well as having closed cicuits with resistance in place for each gauge to ck for stability of gauge when poweer is varied at lamp pin?

[smokinrt]

roger01,

long time since I've talked w/you.  my 69 charger headlamp switch has a pink wire running back to the fuse.  Hope that helps.  I can sympathize with your situation, I'm reinstalling my rebuilt guages, but first need to trace some previous shorts that caused my problems.

Good luck!!
smokinrt
Bryan Simpson
email gets to me sooner
bryanjs@sbcglobal.net

[roger01]

ok heres another attempt to get to the bottom of this .....when the doors are open and the courtesy lights are on ...and i click the dimmer up the dash lights come on and the fuel guage pegs out 
                                                                                 when the door is closed and the coutesy lights are off ....when i click the dimmer up the dash lights come on,and both signal lamps come on ....but the fuel guage doesnt peg out  it just goes to propper level
           can anyone tell me with this extra information what the problem could be .........

[roger01]

i forgot to mention that this is when the dash is out of its position  unscrewed and on the steering wheel