1976 Eldo fuel economy light

[Matt]

The fuel economy amber/green light does not work. I have a shop manual and it does not discuss how to fix it any ideas.

[Lars Kneller 8246]

There is a vacuum switch under the hood on the firewall that operates the light.  Assuming your dash bulbs are good, either it or its vacuum or electrical connection is probably bad.

[EV CLC17806]

MATT:  THE ECONOMY LIGHT SWITCH ON THE FIREWALL CANNOT BE REPAIRED.  YOU HAVE TO LOOK IN HEMMINGS FOR A GUY THAT HAS VARIOUS CADDY PARTS.  I HAVE A 76 CPE DE VILLE THAT I HAD NOTHING BUT PROBLEMS WITH.  I WENT THROUGH A COUPLE OF THEM TO NO AVAIL.  I WAS LUCKY TO FIND SOMEONE THAT HAD A NEW ONE STILL IN THE PACKAGE AND I HAD TO PAY HIM FIFTY BUCKS FOR IT BUT IT NOW WORKS PERFECTLY.  JUST CALL AROUND YOURE APT TO FIND ONE.  GOOD LUCK!  EV

[Tod - North TX CLC]

Before you condem the Vac switch on the economy light, do a couple of quick tests -

The switch has a vac. port and a dual plug with two wires, and the ground is sent thru  these wires to the bulbs in the dash, depending on the vac. that the engine is sending.  To make sure the bulbs and electric supply are ok, unplug the wires from the switch, turn the ignition key to the run position, and using a jump wire to ground, ground each wire in the plug.  The bulbs in the dash should light up - if not, you have bad bulbs or a wiring problem.

If the bulbs are fine, then the problem is in the switch itself.  Since it is grounded to a painted surface, I would suggest that you remove the two bolts that secure the switch, and clean up the mounting surface.  With the switch off the car, you can test the poles using a continuity meter - one pole of the switch should show continutiy between the mounting surface (this will be the amber light - no vac).  If you apply vac. to the switch, you should have continuity from ground to the other pole (the green light).  If not - the switch should be replaced -try your local junk yard - take a continuty meter with you and check out several.  Similar switches were used for several model years, so you might have some luck.

[Matt]

First I cleaned the mounting surface on the switch and nothing happened. Then I gorunded the switch and the amber light did come on but when I ground the other pole the green light dosnt want to come on does that mean the switch is bad and the green light or wiring is bad. I found a switch on ebay for about $35. Any advice would help.
Thanks,
Matt

[Tod - North TX CLC]

Okay - you have determined that voltage supply and bulb to the amber light is good.  If you have cleaned the ground, and the hooked up the wire to the switch, then the amber light should come on with the engine not running.  If that is not the case, then the switch is stuck, and you should consider replacing it (I have not had any experience in opening these switches - some had micro adjustment screws on them, and you might try adjusting these to see if you can get the contacts to seat).  If you dont have access to a junk yard, then the 35.00 switch on ebay might be an option.

This still does not get you out of the woods.  You indicated that you were not able to get the green light to come on, even when you ground the pole directly.  This is the bulb that stays on 99.999percent of the time, so it is possible that the bulb has burned out.  I had a 74 Eldo convertible, but for the life of me I cannot remember if you can access the bulbs by removing the black lens in the trouble light panel, or if you have to take the top dash off to access the bulbs (I think it is the latter - I seem to recall that there is a plastic printed circuit that the bulb socket twists into).  Either way, you need to get to this socket and verify that you are getting voltage, and/or replace the bulb.

Let us know what you find