gnkjoy

Original problem was headlights would all go off when switching to Dim. Corrected that problem now the park lights will not shut off. Headlights function normally. Put in a new headlight switch and have the same results.

Alan 71

Hi g,
There are several ground connections for the forward lighting harness.
On the front side of the core support and on the headlight reinforcement under the front of the hood surround.
Have you checked to see its they're in place?
Regards,
Alan

Front of left side of core support.

lvmyvt76

what corrected the headlight problem seems to have caused your other problem. Did everthing work properly before headlight work was done??

gnkjoy

Ground looks good. However if it was a ground problem I believe the lights would not be on.My problem is the lights will not turn off.

gnkjoy

[QUOTE=lvmyvt76;1592888371]what corrected the headlight problem seems to have caused your other problem. Did everthing work properly before headlight work was done??[/QU]

Everything has worked perfectly for many years. What appeared to correct the problem was to clean the contacts on the light switch and wiring connector along with applying dielectric grease to the contacts.

Peterbuilt

My guess is that the light switch has failed internally.

Alan 71

Hi g,
I believe you'll find that lights like the turn signals, stop lights, parking lamps, and 4 way flashers, that work in conjunction with other lights and switches, can act 'odd' if they don't have their proper grounds.
Regards,
Alan

69Vett

that is correct if the ground is not available, they seek ground thru anything like the lights,
I would suggest unplug the light switch lights should go off if they do, the switch is bad.

65GGvert

Just for grins, check your emerg flasher switch. Is it off? I accidentally bumped mine on and drove with them flashing without noticing, went inside a restaurant and someone came in and told me my parking lights were on. The light switch was off, but park lights on. I finally noticed that the emergency button was on and apparently the flasher contacts overheated and stuck on. When I turned off the flasher switch, everything returned to normal.

gnkjoy

Thanks! Tried that and the flashers work normally. Switched on and off a number of times and the park lights are still on.

gnkjoy

Got a new switch from Mid America. Does the same thing. I suppose it's possible but a real coincidence that one light switch fails and a new one has the exact same failure.
The lights do go out when I unplug the connector from the light switch. Of course nothing in the light circuit works.

65GGvert

It's stating the obvious, but if the lights go off when you unplug the switch, there are only two options. The switch is bad, or miswired. Any chance you took out the old switch and then put it back? Quite a coincidence for two to do the same thing.

Peterbuilt

Lets go back to the last problem, did you replace the dimmer switch?
If yes, check the wires on that.
On the dimmer switch there are 4 wires:
One green goes to the high beam bulbs,
The other green goes to the high beam indicator in the speedometer.
The tan wire feeds the low beam bulbs.
The blue feeds the rheostat in the headlight switch.

Here's a how-to about the headlight switch wires from Willcox Corvette if you need it.





Here's a 71 schematic:
https://docs.google.com/viewer?a=v&p...DcxZjZkOTdhNGU

7T1vette

Just because you don't think that poor grounding can cause such issues doesn't mean that it can't happen...because it does!!

Problem is in the grounds OR you made an error when connecting up the headlamp switch (bad contact, switched wire, etc.). Also a possibility that the 'new' headlamp switch was defective or improperly assembled (by the manufacturer). Today's aftermarket parts are VERY suspect on 'quality'.

65GGvert

The only way you can get parking lights on is to put 12v on the wire. That 12v normally comes from the power source to the headlight switch. If you unplug that connector and the lights go out, that eliminates all other sources for 12v to get to that wire. If it was shorted to another source, the lights wouldn't go out when you unplug it. The dimmer switch has no connection to the parking lights, only the 12v from the switch goes to the dimmer when the headlights are on (and only when on) and then it divides into bright and dim there. It never connects to the parking lights, and even if wired wrong and it did, there would be no 12v with the switch in the parking light position anyway. As far as a ground problem, if the headlight switch is off, there is no scenario where the voltage is feeding back due to a loss of ground, you wouldn't have 12v to feed anywhere. The problem is inside your switch.
Get your old switch and measure from the 12v connector to the parking light connector. With the switch pushed off, you should not have continuity between the two. Pull it on and it should read shorted between the two connectors.
Once you plug that connector back on, the 12v MUST be coming through the contacts inside the switch.

7T1vette

The "man" has spoken.....

65GGvert

Did you reuse the old shaft and ****? Maybe the shaft isn't going in far enough to turn off the parking lights

gnkjoy

I started to wonder the same thing; shaft not going all the way in. However I have removed the switch from the dash. With both on the workbench I can put the ****/shaft in and the switch bottoms out; there is about 1" of shaft showing in the off position between the switch frame and the shaft ****. Also have inserted a long metal rod and can't push it any farther.
When I test the switches there is no continuity between the red (#1 terminal) and the brown (#6 terminal) in the off position. This should indicate the park and tail lights would be off. When I pull the **** to the full on position there is continuity between these two terminals. However at the park light detent I do not get continuity. This does not make sense to me.
The vacuum ports form some function but I assume it is just to open a port to allow the headlight cans to open, not performing any function inside the electrical switch, i.e. the switch is functions the same with the engine not running as it does with it running (with vacuum).
With the electrical connector disconnected there is 12V at the red, orange and white wires.

65GGvert

I can't figure how the voltage is getting to the brown wires connection, yet isn't there with the connector off.

gnkjoy

It does seem like it still has to be internally in the switch. Testing the switch unplugged from the wire harness shows normal function; no continuity between the red power terminal and the brown terminal in the off position. Connecting the wire harness results in power between the red and brown terminals in the off position. Why both switches show the same condition is baffling but there must be some function (relay?) inside the switch. I can identify the old switch as it has overspray from a repaint.
Guess I'll get another switch.
I've been driving this car for 18 years with the only lighting problem being headlights burning out. I have disassembled 95% of the car. The wire harness was in perfect condition with no splices. However I do understand there can still be issues with old wiring. This problem does not appear to be in the wiring.