Dash lights not working

[Damcanadian]

I got a 1969 Roadrunner it has been sitting and trying to get it back to where it should be. The dash lights are not working. A few of the sockets were broken so I replaced all of the sockets and bulbs and none of the dash lights work. My head lights high and low work taillights work turn signals work windshield wipers and dome light work. I replaced all of the fuses and nothing. I tested at the fuse block and I am not getting power to the 3.5a fuse. Where should I go to next?

 

[Yatzee]

Here is a wiring diagram for your car. Open it in a viewer and blow it up in size for reference to wire color codes. About the middle, left side you will see the master connector. You'll have to probe the marked purposes for each contact and work your way back once you confirm the fuses and feed circuit are live. Causes could be: wire burnt off at the back of the fuse box, faulty headlight switch, poor grounds, blown fuse, or corroded contacts at various connectors. You can work systematically from the power source to the illumination end.If you need the other half of the diagram here it is:

 

[Damcanadian]

At the main pin that connects to the gauge cluster should each connector be getting power?

 

[440roadrunner]

The dash lights are a bit of a trick and it pays to understand just how they work

The headlight switch "receives" power from TWO sources........

1....Unfused power from the ammeter circuit powers ONLY the headlights, nothing else. The light switch has a breaker for the headlights

2...The tail fuse supplies a second source to the switch, for tail / park, and dash lights. This power goes through the switch, and through the dimmer, and TO THE FUSE panel on a tan wire.

So in order for the "inst" fuse to have power........

The tail fuse must be good and the tail circuit must operate

The dimmer control must be good

And of course the switch must be in park or "head" and the dimmer turned some to the left

Try working the knob vigorously left to right to clean it. Monitor voltage at the inst fuse while doing so.

AFTER this power finally goes through the inst. fuse, it is then sent out to all dimmer controlled lights on ORANGE wiring, radio, cluster, shift quadrant, etc.

Also, while the diagrams posted are handy at times, they tend to leave some things out. FAR better and more complete are the factory diagrams out of the factory service manuals. You can get both at MyMopar. No, LOL, I don't work there

http://www.mymopar.com/index.php?pid=31

Factory shop manuals for some years. Download Plymouth or Dodge, there is little difference except stuff like Rallye dash, etc

http://www.mymopar.com/index.php?pid=109

Also pay attention to the links for electrical diagrams. Some of these are actually factory wiring out of the shop manuals. Look for "complete" or "Full set" in the link

And this is one of those sets.....

http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerFull.pdf

 

[Damcanadian]

After many frustrating hours I figured out the problem. I ordered new bulbs from rock auto and they sent 194 bulbs and only 158 bulbs will work in my cluster.

 

[440roadrunner]

Well that's not true. The 194's are a little more wattage but they should work. Something else is going on. Might just be corrosion in the sockets or where they contact the board.

 

[Sixpactogo]

If you are not getting power to the 3.5a fuse, it is not the bulbs. My guess is the variable dimmer switch has failed. They are a rheostat that varies the voltage sent to the fuse and they get corroded. Check there first. If the rheostat is fine and voltage is getting through then you could have a broken wire or blown fuse. I would bet it is the rheostat.

 

[70DartMike]

Do you have a good ground to the circuit board? They were only grounded through the screws that attach the cluster to the dash. Over the years they get dirty and corroded. I always run a separate ground from the dash frame to the back of the circuit board. You want to use one of the screws which holds the circuit board down to the gauge housing, not one with copper under it. I use a male/female connecter in the middle for ease of removal down the road.
I did this on my '70 Dart, '65 Valiant, and '67 Barracuda. Dash lights didn't work on all 3, now they're nice and bright. Other misc things back there started working too.

 

[Damcanadian]

Ok thanks for all the tips. I've replaced the fuse and the dimmer switch. The only bulbs that work are the 158. I tested the orange wire on the main plug and have power, I didn't thing the points or board were corroded. I will post pics to make sure that I'm not missing something.

 

[Sixpactogo]

The tan wire coming off of your panel dimmer switch feeds the 3.5a fuse in your fuse box. If you have power there and your orange wire has power, then all it can be is bad bulbs, bad ground at your cluster or corroded sockets.

 

[Damcanadian]

I have replaced all the fuse and have power at the fuses, the orange wire has power, replaced the dimmer switch all exterior and dome lights work.

 

[440roadrunner]

I hope you still have the cluster out, HERE is what you should do.........

Clean around the harness connector pins and solder them to the board

See the contact finger there for the instrument limiter? You should clean that and solder a jumper across the between the contact finger and the board trace.

Nuts on the gauge studs........consider replacing with "real" nuts, or even if not, loosen / tighten them a couple of times to "scrub" the connection and make sure they are actually tight.

Lamp socket contacts. Those copper board traces are heavily oxidized. Take a big eraser and scrub the copper a bit until it brightens up

This is an A body panel, but shows the idea

http://www.forabodiesonly.com/mopar/showpost.php?p=1969970136&postcount=16

 

[Damcanadian]

Ok so I cleaned all the copper soldered like in the link. Nothing changed I get one illumination light the brake light works but no other dash lights work. I took a voltage meter to check all the circuits on the board and they all cam back fine is this a connection with the main plug on the harness? Should I take out the connectors and manually plug them to make sure there is a solid connection? Where exactly are you talking about putting a jumper, and what will that do?

 

[440roadrunner]

Check the link I posted. It's where the IVR contacts which are brass springs are pressed into the board. They don't always (anymore) make contact with the board traces. This is preventative, nothing to do with your lights.

What MIGHT do with your lights is the harness connector pins I mentioned.

If the board "ohms" out OK, it is likely elsewhere

Make sure you install aground pigtail. In the photo you posted just above, the hex head screw EG is a good place to connect a grounding wire.

I would "jig" it up out of the panel or in other words just hang it in there enough to hook it up. Be careful of the ammeter wires. If it won't work

Put your meter "clip it" to the orange wire down there at the fuse panel and "play" with the dimmer. If you get voltage at the orange wiring in the fuse panel and no dash lamps, then it either is a poor connection "in those" orange wires in the panel, or a bad connection at the cluster harness connector, or you've missed something there on the board, such as a connector pin

(Bear in mind electrons flow neg to pos) but the "circuit path" for dash lamps is...........

Battery..........harness........fuse panel.........tail lamp fuse..........light switch........dimmer control.........out on the tan wire back to the fuse panel...........through the "inst" fuse..........and out to lamps on orange wires, radio, heater, console..................one orange goes up to the cluster connector..........and to the harness pin there on the board.

That is the "path."


It does not seem reasonable that every single cluster socket is bad, or bad bulbs, or not making connection. HOWEVER it is actually possible. Clean the copper there on the board where the sockets fit.

 

[Sixpactogo]

It is starting to sound like the orange wire coming off of the 3.5A fuse has an open in it. If you have power to the fuse and no panel lights you need to trace the orange wires down to see where the open is. It can't be shorted of you are not blowing the fuse. The brake light that is working is not on that circuit.

 

[440roadrunner]

It is starting to sound like the orange wire coming off of the 3.5A fuse has an open in it. If you have power to the fuse and no panel lights you need to trace the orange wires down to see where the open is. It can't be shorted of you are not blowing the fuse. The brake light that is working is not on that circuit.

That might be but very doubtful that it's "in the wire" far more likely it's at a CONNECTION.

Which is why I mentioned check the orange wires right there in the fuse panel. I believe they are riveted. "Wiggle test." And check the connector / terminal right there at the PC board connector and pins.

 

[Damcanadian]

After much disappointment and now a few beers my dash lights are still beating me up. The only lights that work on the dash are one light above the odometer and the brake light. I scrubbed all the copper, replaced every screw on the back of the gauges, tested every socket and light bulb, tested the circuit board. I did buy a restored dimmer switch, or could it have any thing to do with the alternator? I check the 3a fuse at the block and it zeroed out the ohm meter but, the connection on the back where it is riveted does wiggle. I hooked up the ohms meter to the main plug in every possible way. All of the test were done with the dimmer wheel all the ay before it turns the dome light on.

no cluster just power cluster ignition off cluster ignition on
1 orange - Instrument lights 0.00 -3.22 -3.43
2 blank
3 red - high beam indicator 0.00 -4.75 -4.74
4 light green - left turn signal 2.54 -4.75 -4.79
5 dark blue - gas gauge 0.00 -4.74 -4.75
6 dark blue - brake light 1.52 -4.78 -4.77
7 dk-bl-tr - gauge feed 0.00 -4.74 -3.75
8 gray - oil pressure indicator Did not register -2.22 11.30 (bounced)
9 violet - temp gauge 0.00 -4.74 -4.74
10 tan - right turn signal 0.00 -4.78 -4.75

 

[440roadrunner]

Well you are not listening.........test this under "as close to" operating conditions as possible. Sounds to me like it's right there in the fuse box.

To repeat..............

The tail fuse must be good and the tail lights must be working

The light switch must be in park or head

The dimmer must be twisted "to the left" and PLAY with it as it may not be making contact

WITH at least some lights (the cluster, or the radio and shift quadrant, etc) hooked up, measure voltage at the INST fuse ON BOTH ENDS. If the wire / rivits are loose, then figure that out, it is PROBABLY the trouble.

Depending on "what lamps" are hooked up, BOTH ends of that fuse should go up and down in voltage as you twist the dimmer. With dimmer "to the left" you should get 10-11V or maybe more.

 

[65-440]

I'd check that fuse box as well. I had the same problem with my coronet a while back. 2 problems actually. wiggle that orange wire on the back of the fuse box, probably a bad connection there. my 2nd problem was the turn signal fuse was not making a good connection and would get hot and start to melt the plastic box ! The fuse box is a non-moving part but **** does happen !

 

[Damcanadian]

I cleaned the connections on the fuse holders and crimped them tight. Now the right side of the gauges work, but the left side does not. The passenger side turn signal works but the driver side does not. Also the lights are dim, and the driver side turn signal is slow unless I increase the rpms. Is this a bad ground, battery, alternator or something major electrical still?