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Discussion Starter · #1 ·
okay so iv hadda problem for a few months now...if i flip my switch to turn on parking lights nothing happens, but if i turn to headlights my lights turn on (all lights).

i did some research on here and roadie mentioned something about rear fuse 36...i went out to check and all fuses for parking lights were still in working condition

while checkin out the other fuses, i removed fuse #30 (big gray one) cause i couldnt remove the others...my fingers are too fat :worried:

coudnt find the problem, reinserted #30 sealed everything back up and walked away only to notice that now my parking lights are on. all switches are off, power cut, but yet the parking lights are on....the ONLY way that they will turn off is if i remove rear fuse #30 (the big gray one) :hopeless

someone help please :bonk:
 

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Well, they call it a fuse, in the owners manual, but your big grey fuse #30 is a relay. It is the parking light relay.
This relay, when operated, turns on the parks. It is operated by the body control module.
The BCM is directed to operated the relay when a "I am turned on" signal from the headlight switch.
So, the problem is either a faulty relay, or a faulty switch.
going back to the start of your post, "no parks in the park position, but parks in the headlight on position", I would guess a faulty switch.
When you pull the relay out, do you hear/feel a slight click. This is the relay operating. If there is a perceived click, the relay is good. No click, the relay is stuck in the operate position and is faulty.
 

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Discussion Starter · #5 ·
flip the relay around to reverse todays changes
already tried that :crazy:

Well, they call it a fuse, in the owners manual, but your big grey fuse #30 is a relay. It is the parking light relay.
This relay, when operated, turns on the parks. It is operated by the body control module.
The BCM is directed to operated the relay when a "I am turned on" signal from the headlight switch.
So, the problem is either a faulty relay, or a faulty switch.
going back to the start of your post, "no parks in the park position, but parks in the headlight on position", I would guess a faulty switch.
When you pull the relay out, do you hear/feel a slight click. This is the relay operating. If there is a perceived click, the relay is good. No click, the relay is stuck in the operate position and is faulty.
the relay does still click. nothings been wrong untill i took it out today...if i take out the relay and turn on my headlights, my parking lights dont go on and neither do any of my rear lights...should i go buy a new relay? i now have to put it in/out everytime i getin in...i even tried flipping it around and it does the same thing...:sadcry:
 

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already tried that :crazy:



the relay does still click. nothings been wrong untill i took it out today...if i take out the relay and turn on my headlights, my parking lights dont go on and neither do any of my rear lights...should i go buy a new relay? i now have to put it in/out everytime i getin in...i even tried flipping it around and it does the same thing...:sadcry:
If it's clicking, the relay is being operated by the BCM. The relay is probably ok.
I think you have a bad switch. You should be able to unplug the harness from the back of the switch (you'll have to remove the lower part of the dash to get to it), if the lights go out, after unplugging the switch, the problem is probably in the switch.
 

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Discussion Starter · #7 ·
If it's clicking, the relay is being operated by the BCM. The relay is probably ok.
I think you have a bad switch. You should be able to unplug the harness from the back of the switch (you'll have to remove the lower part of the dash to get to it), if the lights go out, after unplugging the switch, the problem is probably in the switch.
hmm im thnkin yeaa...cause another thing that happens to me is that if i turn the switch to the left, it turns orange...but then if i turn on the headlights the left LED turns green, and the orange one doesnt go off only dims :hissy:

its dark but im gna go and disect my dash and see wat i can come up with :suicide:
 

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Discussion Starter · #9 ·
according to this diagram, if the relay was installed backwards, power would be applied to the running lights at all times
even with the relay reversed, they still dont turn off...just constant power
 

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according to this diagram, if the relay was installed backwards, power would be applied to the running lights at all times
Not quite. I was curious, so I started researching the various relay pinouts. I think the schematic is not the physical orientation of the contacts, which for this version at least, are rotationally symmetrical. It can be in backwards and still work as expected. Still researching.
 

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Discussion Starter · #13 ·
afternoon bump?

its been raining all day and im still at school so im not tryin to sit out in the parkinlot to check the switch but i have the relay out so that my lights are out while parked.
 

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Discussion Starter · #14 ·
okay so checked out the relays...thas not the problem...now wat should i do :confused:
 

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Tell us what voltages you find at each of the four terminals on the relay socket, with the ignition off and the relay installed. This isn't always an easy trick to pull off, but I usually take a 6" piece of thin wire, like 28-30 gauge, strip 1" off each end, and wind a turn around each of the relay blades, then install the relay. Then you can get a meter to read the voltage while the circuit is running.

I, like Ray, am leaning towards a bad headlamp switch, except I can't explain why the BCM isn't disabling that relay control signal when the ignition's off.

How exactly did you confirm the relay is OK? With a meter, a 12V source, and some jumper clips?
 

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Discussion Starter · #17 ·
How exactly did you confirm the relay is OK? With a meter, a 12V source, and some jumper clips?
i went (well my buddy did) went to the fuse box under the hood, where there are 4 more relays with the same number setup. he took out one of the relays from the front and put it into #30 in the rear and as soon as he inserted it the lights turned on again...we then tried a 3rd relay only to have the same effects...so we concluded that it was not the relay that was causing the issue...we then re-installed all the relays to where they were originally and nothing changed...the relay is in my truck disconnected. another weird thing...i can turn on my headlights and they come on but they come on without the parking lights front or back, but the brake and blinkers still work, and so does my led strip on the back :worried:
 

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Not quite. I was curious, so I started researching the various relay pinouts. I think the schematic is not the physical orientation of the contacts, which for this version at least, are rotationally symmetrical. It can be in backwards and still work as expected. Still researching.
Sorry guys, I missed this thread being updated.

Yeah, most of the relays (like the 3157 lamps) are designed so that they will work plugged in either way.

Note, I said most. There may be some that need to be plugged in correctly.
 

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And I have not been able to find a pinout for the relay:hissy:
Top view of the socket:

87 86


85 30


The coil is 85-86, contacts are 30-87. Memorize this. There will be a monthly quiz. That's why it's rotationally symmetrical, because this version of the relay has no safety diode on the coil. And no NC contact.

For extra credit, explain why relay coils often have a diode across them. :D
 
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