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The next thing you might want to check is the headlight switch connector.
Remove the wires and see if the connector melted and shorted the orange wire to the brown.
The next thing you might want to check is the headlight switch connector.
Remove the wires and see if the connector melted and shorted the orange wire to the brown.
The vacuum hoses are only to open and close the headlights.
I removed all wires and cleaned them with a Scotch pad. No burning indication and the white connector looked perfect, i.e. no melting or burns. Reassembled and still have the same condition; park lights will not shut off.
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.
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.
Thanks. I have performed that check. Both old and new switches show open circuit between red power terminal and brown light terminal with switch in off position. When either switch is plugged in there is 12v at the brown terminal in off position. I have removed each wire from the connector, cleaned them and used Scotch pad on the terminals. Wires all look good as does the connector; no signs of burning or melting.
Another thing pointing to being a switch problem is that there is no continuity with the switch in the park light position; only when in the pulled all the way out in the headlight on position. However both switches have the same condition.
Just talked to Mid America and they have authorized a return and are shipping a new switch today. I will report back when after trying the new switch.
Since both switches are acting (and check) the same when out of the car...but problem was with only the later switch...what I posted in post #14 is still applicable:
1.) you have a grounding problem that is allowing 12v to feed into the parking light circuit (could have been caused when you worked on the switch);
OR
2.) working on and around the switch, some electrical circuit/wiring/ground got changed, damaged, or swapped by accident.
Are you absolutely sure about where to connect each wire to the headlamp switch? Your problem could easily be a mispositioned or swapped wire.
Thanks. I have performed that check. Both old and new switches show open circuit between red power terminal and brown light terminal with switch in off position. When either switch is plugged in there is 12v at the brown terminal in off position. I have removed each wire from the connector, cleaned them and used Scotch pad on the terminals. Wires all look good as does the connector; no signs of burning or melting.
Another thing pointing to being a switch problem is that there is no continuity with the switch in the park light position; only when in the pulled all the way out in the headlight on position. However both switches have the same condition.
Just talked to Mid America and they have authorized a return and are shipping a new switch today. I will report back when after trying the new switch.
Since both switches are acting (and check) the same when out of the car...but problem was with only the later switch...what I posted in post #14 is still applicable:
1.) you have a grounding problem that is allowing 12v to feed into the parking light circuit (could have been caused when you worked on the switch);
OR
2.) working on and around the switch, some electrical circuit/wiring/ground got changed, damaged, or swapped by accident.
Are you absolutely sure about where to connect each wire to the headlamp switch? Your problem could easily be a mispositioned or swapped wire.
I am sure about the wire connections. I never removed any wires until today. Also, both new and old switches exhibit the same conditions.
I believe as 65GGvert stated; a grounding/short circuit condition should yield park lights on even if the wire harness is disconnected from the headlight switch. In the off position and disconnected the switch does not have continuity between the red power wire terminal and the brown park/tail light terminal. If it's open how would you see 12v at the brown terminal by plugging in the connector. It seems logical that the short circuit is in the switch. Am I missing something?
I am sure about the wire connections. I never removed any wires until today. Also, both new and old switches exhibit the same conditions.
I believe as 65GGvert stated; a grounding/short circuit condition should yield park lights on even if the wire harness is disconnected from the headlight switch. In the off position and disconnected the switch does not have continuity between the red power wire terminal and the brown park/tail light terminal. If it's open how would you see 12v at the brown terminal by plugging in the connector. It seems logical that the short circuit is in the switch. Am I missing something?
No. If it was me, the switch would be the next thing I'd try. I believe you're getting 12v through the contacts in the switch, it's the only thing that makes sense when the lights go off when you unplug it.
No. If it was me, the switch would be the next thing I'd try. I believe you're getting 12v through the contacts in the switch, it's the only thing that makes sense when the lights go off when you unplug it.
While waiting on the new switch I decided to take apart the original one. As you can see this is just a mechanical contact switch. There was a lot of grease on the contacts so I cleaned everything with acetone and Scotch Brited the contacts. I reassembled the switch and plugged back in. Same result; park lights do not shut off.
The one thing I don't fully understand is the contact point arrangement on the for the red (power) terminal. Can't see anything that would cause it to be open. What is the purpose?
So now I don't believe a new switch is the answer. One question is does the switch itself require a ground? I don't see it by the wiring diagram.
The grease that was in there is a dielectric grease. It is intended to keep air from reaching the contact points so that they don't 'burn' from arcing. Don't remove it from the new one you receive.
After reviewing the electrical schematic for the Corvette, I do not believe there is a ground going to the headlamp switch.
The contact at the end of the rheostat for dash dimmer touches the bracket and grounds it to turn on the interior lights when fully rotated. I don't see how that can affect the parking lights. I wish you were close by, I think we could put a voltmeter on that brown wire and start eliminating sources where it can get 12v.
I made an edit to the contact to the dash dimmer grounding.
The metal part of the headlight switch picks up a ground through #7 but that only comes into play when you turn the shaft all the way to the left to turn on the courtesy lights.
I'm assuming your side marker lights stay on also?
I know you've tested it, but it really sounds like the shaft isn't opening the contacts when you push it to off. That's all I can think of that would make your emerg flasher work normally, lights normal, and park lights go off when you unplug the connector.
If I understand correctly, it worked until you corrected the dimmer issue. Exactly what did you do? I'd disconnect the dimmer completely. There's no connection I can see, but I'd be desperate by now.
Thanks. I have performed that check. Both old and new switches show open circuit between red power terminal and brown light terminal with switch in off position. When either switch is plugged in there is 12v at the brown terminal in off position. I have removed each wire from the connector, cleaned them and used Scotch pad on the terminals. Wires all look good as does the connector; no signs of burning or melting.
Another thing pointing to being a switch problem is that there is no continuity with the switch in the park light position; only when in the pulled all the way out in the headlight on position. However both switches have the same condition.
Just talked to Mid America and they have authorized a return and are shipping a new switch today. I will report back when after trying the new switch.
I keep going back and reading this. If there is no continuity in the park position, I wonder where it's getting the 12v to light them when you're in park. It has to be the same place you're getting it when switch is off. But WHY is there no continuity? And where is it getting 12v that disappears when you pull the connector? I'm afraid I have all questions and no answers.
Try a quick check of the Willcox diagram that Peterbuilt posted and make sure you have the correct colors of wires in the correct slot. Possibly what you're measuring for the contacts that go to the brown wire are not actually the correct contacts.
As Foghorn Leghorn says to the little chicken, "I say, I say, it just doesn't add up".
1)OK- lets try to figure where problem is coming- the front of the car or the back.
Try disconnecting the 12 pin harness ( 8 wires on it) that runs to the rear of the car- that way you'll know which tail to chase. Located above the fusebox- what it looks like-see below
2) Where's the constant power coming from? Actually pull the hazard flasher - as it has constant power and the parking lights might not pull enough power to flash. Then pull fuses-till the lights go out.
1)OK- lets try to figure where problem is coming- the front of the car or the back.
Try disconnecting the 12 pin harness ( 8 wires on it) that runs to the rear of the car- that way you'll know which tail to chase. Located above the fusebox- what it looks like-see below
2) Where's the constant power coming from? Actually pull the hazard flasher - as it has constant power and the parking lights might not pull enough power to flash. Then pull fuses-till the lights go out.
Lets us know-
I had the exact symptoms on my 68 Camaro last week. As I said earlier in this thread, my emergency flasher was stuck. I had bumped it on with my knee and didn't notice. After a while, the park lights just stayed on continuously and wouldn't turn off. After I turned off the flasher switch, they stayed on until I thumped the flasher and then everything went back to normal. Between us we sort of eliminated the flasher since it worked and turned off normally. That's a good idea to unplug it to see if it may be passing enough current to light the lights.
Turn signal flasher module is behind the right-side passenger dash pad (low and to the right). Yes, your problem could be a bad flasher module that is locked in the ON position...but only if the flasher **** has been pulled.
However, if the flasher module has failed in the ON position and the flasher **** has NOT been pulled, I'm not sure what result you would get. The module (which feeds the parking & tail lights) would be in the ON state even though power should not be going to it. Would that set up some kind of weird power routing? I don't know...
The emergency flasher is the one that plugs into your fuse panel. It's the one that's powered with ignition off and the one you should pull. It's a long shot, but it will eliminate one more thing.
08-21-2016, 04:53 PM
