Hi Dalton here,

I've owned a 1963 Riviera for about 2 months now. Lots of work to date and beginning to make some progress with maintance and repair items. I do have a manual and have studied it extensively BUT I'm not a skilled mechanic.That said, I am trying to do all the work myself.

I've observed a few odd things with the instrument panel lights and hoped someone might have a clue or two about possible solutions.

When the headlights are on there are no insturment lights unless I turn the reostat all the way up. When the lights are on, the "red" bright indicator is dimly illuminated. As background, the previous owner (a ROA member) mentioned that he did not like the Guide-o-Matic so he by-passed it and ran a different headlight bright switch as well. Brights do seem to work alright most of the time but sometimes the dimmer floor switch has no effect - I'm assuming it's dirty and not making contact.

When the reostat is all the way up, then the following is observed: Some of the dash and instrument lights come on, i.e. shifter, light over the AC/Heat controls and at least two of the insturment panel lights (speedo and clock but the clock has no power at this time on that circuit - I assume the other bulbs are burned out). BUT both blinker indicators turn green and the gas gauge moves to E immediately. If I remember the manual correctly, it seems the gas gauge has lost it's ground as I believe that F is full ground (but perhaps I have it backwards). If I turn the reostat off full, then the lights go off and gas gauge returns to previous position.

The other odd thing. When the headlights are off but a turn signal blinker is on, the gas gauge drops about a 1/4 tank and bounces as the blinker cycles.

Another piece of data. The previous owner had a nice collection of spare parts he gave me with the car. One of those parts was a spare circuit board for the panel lights. Maybe I should ask him about that as well???

Any clues as to why I might be getting these odd things happening when I can get the reostat switch to light the panel lights?

PS - One more while I'm listing questions. The speedo bounces but only around 1 to 10 MPH then by 15 to 20 MPH it's smooth. I've not yet tried pulling the cable and lubing but wanted to know if I should check something else.

Thanks in advance.

Dalton,

If I were in your shoes, I think I'd get rid of the "by-pass" the previous owner put in and go back to scratch. Can you recall if their was a technical problem with the guide-matic or if the owner just didn't like it. Mine is not enjoyable when it raises and lowers the hi beams everytime I go under a street lamp. There's a reostat on the back of it that allows you to turn it off or adjust the sensitivity. There's also an over ride built into the floor dimmer. Depress it half-way and you can over ride the guide-nmatic.

I would imagine that the owner tied the new switch into a circuit and creates a ground issue that affect the other lights.

Good luck on this one.

Ed

I agree with Ed that it sounds like a bad ground on your instrument panel board. A large plug attaches to the back of the board, from the wiring harness. One of those wires is a ground. You could try jiggling that plug and make sure it is seated well.

One of the neat things about ground wires is that you can always just add another one. Find a ground point anywhere on the panel and add another lightweight wire from there to any other screw or nut under the dash.

I don't think you have to undo the previous owner's work to fix this.

Thanks Jim and Ed,

Due to the fact the previous owner supplied me with many extra parts, including a NOS circuit board, I was able to study the board and discovered that one of the 3 brass mounting connectors felt as if the mounting screw had snapped off and therefore was not making a good ground (these are also 3 individual grounding circuits in addition to the ground on the main plug - not all the ground connect to one another as far as I can tell). The reason I think the screw had snapped off is I could not get a new screw to tread, it felt as if something was blocking it. So I tapped into the ground circuit on the board and now ALL the dash lights work!

If anyone wants a picture of this board for your reference, let me know - being able to trace the circuit made all the difference as all the lights not working were on the same ground circuit!

PS - Ed, thanks for the suggestions.

Dalton,

Sent you a PM.

Ed