Maxdaddy1$
New Member
I have no dash lights on my 68 Newport.
Anyone have a good diagnosis plan to id the problem?
Anyone have a good diagnosis plan to id the problem?
Okay, where can I provide the history? I did add a photo as a profile pic just now.first post, we must see a picture of your car and some history, we are a demanding group
here is fine, just a thread describing your experience on finding and cars history will be fineOkay, where can I provide the history? I did add a photo as a profile pic just now.
Map light comes on when I turn it all the way up.I would check the dimmer switch first.
Map light comes on when I turn it all the way up.
Wow, great advice. Hope I have the skills to do all that. Many thanks.I have a '68, and have worked on the instrument panel lighting a bit myself. If you have the map light when you click the dimmer all the way, then the dimmer is still good.
NOW, you will need to remove the instrument panel for deeper analysis: Download the FSM if you haven't got one. The 1967-68 dash is EASY compared to their lovely but inconvenient forebears of '65-66! You can just unscrew the sundry bezels, faceplate screws and finally the instrument panel screws themselves, and pull them out!
Have at the very least, a test light when you do this.
Your instrument panel has a crude voltage divider to supply much of the instrument lighting. Start by testing current IN to that. The dimmer varies 12V, as can be seen when the map light comes on as you peg it. The wiper and spring on the dimmer accumulate dirt and oxide over the decades, and a bit of good contact cleaner is best used to restore it to functionality. Get some, and some sort of applicator to clean the spring GENTLY. If the map light contactor still closes, as yours does, then the odds are high the dimmer is still GOOD.
SO, you must test the voltage of the power supply! Find it, ground the portions of the dash with alligator clips if they're not in contact with the frame, then test power IN to the voltage divider/power supply, and test what comes OUT of it.
I suspect, given what you described earlier, that THIS may well be the point of failure. If you got this far, replace it with a solid state one! They run around $50. I need to do the same, FWIW....
Lack of proper GROUNDING often causes instrument panel lighting failure. You will have plenty opportunity to correct this now. For the purpose of testing the panel, you can actually remove the whole damn thing to a bench w a power supply, and test it there, but if it isn't grounded well to the frame, it still won't light up. I make bonding jumpers for stuff like this from stranded copper wire and some good lugs. Easy to do, well worth the trouble.
Van carries a solid state power supply for the instrument lights: Fits Dodge Chrysler Plymouth Solid State Voltage Limiter NEW | eBay
If the map light works, but the dome light doesn't, there's wiring issues somewhere. Also, the map light is a simple on/off as the rheostat wheel is turned and not part of the wiper or rheostat coil. The coil or wiper on the rheostat could still be bad (or dirty). It does show that there is power to the switch though.If you have the map light when you click the dimmer all the way, then the dimmer is still good.
The voltage limiter is for the gauges. Basically dropping them to 5 volts. It has absolutely nothing to do with the instrument lights. It is a good upgrade, but not part of the OP's problem.Van carries a solid state power supply for the instrument lights: Fits Dodge Chrysler Plymouth Solid State Voltage Limiter NEW | eBay
Did you do what I suggested and work the switch back and forth? It's the simplest check that you can do.Map light comes on when I turn it all the way up.
Yah. There IS power TO that switch. I suggest cleaning it well. Contact cleaner and q-tips if necessary, making sure to remove every cotton fiber after using them. Mine does decent thus. Won't hurt to put LEDs into the instrument panel also. Reduces current demand all around.If the map light works, but the dome light doesn't, there's wiring issues somewhere. Also, the map light is a simple on/off as the rheostat wheel is turned and not part of the wiper or rheostat coil. The coil or wiper on the rheostat could still be bad (or dirty). It does show that there is power to the switch though.
The voltage limiter is for the gauges. Basically dropping them to 5 volts. It has absolutely nothing to do with the instrument lights. It is a good upgrade, but not part of the OP's problem.
Wow, great advice. Hope I have the skills to do all that. Many thanks.
I had the same issue with my '66 Newport, I'm not sure if your '68 is wired the same. I thought I was going to have to take out the steering coumn and dismantle the dash ( because it has air conditioning). My map light and dome light both worked. I changed the headlight switch and Ihave dashlights!