Parking lights stay on

Hey Gang,

I have a strange occurrence with my 98 Explorer Sport. All of the sudden my parking lights will not shut off. The headlights work fine, but I cannot get the parking lights to turn off. The only way is to pull fuse #11 under the hood. I even pulled the headlight switch and they still stay on.

I don't have any fog lamps or trailer hitch wiring on this truck. It's just the stock lighting.

Any ideas?

Jaime

If it is the brake switch how come the front parking lights also won't shut off? How is the brake switch wired to these? It shouldn't be.

KA3NXN said:

If it is the brake switch how come the front parking lights also won't shut off? How is the brake switch wired to these? It shouldn't be.

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????? who said it was the brake switch????

sounds like a relay sticking. Locate the parking light relay and switch it with another and see if they work correctly

Where in God's green earth is this infernal parking light relay? I have torn my dash apart and found one lone relay behind the left side of the passenger's side airbag. I pulled every relay in the main power box under the hood on the driver's side. I also found a bank of relays on the passenger's side under the hood down low. None of these seem to effect any of the lights.

KA3NXN said:

Where in God's green earth is this infernal parking light relay? I have torn my dash apart and found one lone relay behind the left side of the passenger's side airbag. I pulled every relay in the main power box under the hood on the driver's side. I also found a bank of relays on the passenger's side under the hood down low. None of these seem to effect any of the lights.

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check the light switch, check the head light switch, they do go bad. and burn up, also the connector.

quick question do you have auto lamps?

never mind it has a park lamp relay.... its located.... i'll get back to you once i find the location.

behind the center of the dash what looks like the drivers side right leg, is a small box with relays in it, should be in that area.

I pulled the light switch and it is sitting on my kitchen table inside the house and the parking light still stay on. The harness looks fine. The only way to get the light to turn off is to pull the #11 fuse under the hood or to pull the positive terminal on the battery. One strange thing that I found though. For giggles and laughs I put my volt meter where the #11 fuse goes under the hood and I am reading battery voltage in the fuse connector with the fuse removed. I should not read battery voltage across a fuse connector. The fuse should only complete a circuit on the positive leg of the circuit. This makes no sense. I do not have auto lamps

????... maybe a measurement problem.... I am confused though as you said that pulling the fuse turns them off BUT that you measure "some voltage" on the "other side" of the fuse block (the load side).... if indeed that was the case, pulling the fuse should / would do nothing since you are still "seeing" 12v. As suggested, instead of pulling the fuse, pull the park lamp relay and observe the effects and go from there.

Well I have good news and bad news. The good news first: I found the parking light relay. Now the bad news: The problem is not with the relay. It's the same type of relay that I have under the hood and I tried replacing it with one of those and the problem still persists. At this point the only thing is to start tearing into the wiring harness. Any other ideas?

http://imgur.com/a/V1Bzy

check the tow hook up in the rear they corrode and i think also have constant power which can jump.. anyway the 2 diagrams that show how it works.

do you have an alarm? factory or aftermarket...

I don't have a towing package on this truck.

.... BUT... what happens when you pull the relay????

When I pulled the relay, the lights did go out. That's how I knew I had the right relay, finally.

OK... now you have found "most" of the problem.... check the electrical conditions going to the relay. Is it operated???? then if so, why... probably cause it has a voltage going into the coil.... why? trace that back.

From the diagram I see one side of the relay coil goes to fuse #11 which is the fuse that I pull and the lights ago out. So this makes sense. The other side of the coil goes to this (RAP) Remote Anti-theft Personality Module. What and where is this RAP module? I don't have any anti-theft system in my truck. My truck is pretty plain. It's a 2wd sport model, no cruise control, no fog lamps, no daytime running lights, no anti-theft system, no keyless entry, no towing package. I guess I should list what I do have, it's a shorter list. It's basic, power windows, rear defrost, AM/FM CD player, nothing else.

KA3NXN-- When you bridge the fuse gap with your meter, you are reading VOLTAGE DROP. Since the circuit is broken with the fuse removed, until the meter is placed across the terminals, there is no connection from one side to the other.

When you connect the meter, the voltage is dropped across the very high resistance of the meter (somewhere around 1 meg-ohm per volt for most meters). The resistance of the meter swamps the circuit, so the current is infinitesimal, but Kirchoff tells us that the sum of the voltage drops must equal the source voltage. Since the meter resistance is essentially the whole resistance, the meter tells us that the missing fuse is dropping the entire voltage...this is as it should be.

As to the short, crack open the harness that goes to the light switch. You are likely to find burnt insulation on several wires, one of which is shorted to +12V, and is feeding the relay for the parking lights. Ford still uses a 'hot' headlight switch in that circuit, instead of the grounding switches more common these days.

OK... but you need to find out whether you are chasing a "voltage is there" issue or a "ground is there" issue. Further looking at the circuit, you are chasing a "ground is still there" issue (although the schematic that I see isn't very clear / good). The ground of course, could be in the form of a "shiner" (insulation missing and wire touching a bit of metal).

I'll have to start peeling back some of the tape on the bunched up wires from the headlamp switch connector on back. At all the connectors so far they look pristine. No signs of insulation damage not even heating. So now I start peeling back the taped up harnesses. I was hoping it wouldn't come to this.

The wire in question goes from the switch to the hot side of fuse 11; try disconnecting it from the fuse and see if the lights go out. If so, just cut that wire at both sides, and run a new wire outside of the loom.

It is NOT a "hot" problem.... its a grounding issue on the relay coil.....

Update.... I back track..... check the coil for both voltage and ground.