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Discussion Starter · #1 ·
Hello Fellow Members!

I recently have been working on installing these OEM lights into my aftermarket bumper. I did my own research across many pages, forums discussions, youtube videos, etc, and made this plan:
(I apologize now for incorrect terms as I have almost no knowledge of electrical wiring or anything related)

5pin rocker switch installed inside the main console.

Switch is connected to a 4 pin Relay (specifically connected to pin 86).

Relay installed under the hood to prevent any fires inside the console and grounded to the chassis where the paint was sanded off(pin 85).

The two power wires for the light bulbs conjoin and connect to the relay (pin 87).

The Ground wires for the light bulbs both connect to the chassis or T-tap into a wire already grounded.

I then connected power from the battery to the relay power with an inline fuse of 10Amp(pin 30)

The 5 pin rocker switch is powered by an ada circuit in the fuse box (to the rocker's pin 2)

The switch has another pin (6) which illuminates the words "fog lights" once it is activated- this is connected to a t tap into the dash's 12V power wire.

The switch's pin 3 is where the relay is connected- this pin sends power to turn on the relay in pin 86.

The last two pins on the switch are 7 and 8 which are both grounded.




NOW I know that is a lot and hopefully not too confusing, I will add in some pictures of my wiring circuit and how the pins work just to help clarify.

Here is my problem:
So after finally wiring this all together the lights worked and ran fine. Then I was using them and the fuse blew out so I replaced it and turned on the lights to make sure everything worked and they seemed to work fine once more. While I was watching the lights to make sure they worked, the fuse blew out again. I have tried using several other fuse sizes up to 25 amps (as the relay is safe to 30 amps total) and each fuse keeps blowing out almost instantly. I do not know what to make of this or what to change, the connections are all still connected and look pretty solid. However the lights will turn on for a split second before the fuse blows, but for some reason I can't seem to find a way for the fuse to not blow out every time I try to use the lights. The switch is all connected correctly and the relay will turn on and off via the rocker switch. The switch still illuminates and all that fun stuff so those pins are all still correct, however the lights are just causing blow outs.

If anyone knows has an idea of what an issue could be I would greatly appreciate the time and help!!

-Below are images of the diagrams, switch on and off, and the lights working as proof that they did work at a point in time XD
 

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Do you have a diagram for the rocker switch? The relay looks right.

Here is a diagram for the OEM switch. I'm still digging......

I went straight to the relay from the battery (20 amp fuse) and used the "from 12v switched". (skipped the optional fuse panel connection)

Pin 3 is 12v in
Pin 4 is 12v out to relay
Pin 4 connected to pin 1 to turn on the LED indication switch is on
Pin 2 is ground for the ON LED
Pin 6 is from the dash light rheostat (dimming)
Pin 5 is ground for Pin 6 LED

I tied pin 2 and 5 (ground) together.

Relay:
12v from battery/20amp fuse to pin 30, Pin 87 to lights
Pin 85 and 86 looking for my diagram of the relay for which is from the switch and which is ground

Text Line Diagram Parallel
 

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Your wiring sketch is correct, but you may not actually have wired it per your sketch. That fact that you blow 25A fuses instantly implies that you have a intermittent dead short somewhere, or that the bulbs installed in the lights draw significantly more than 25A.

Are these new or used lights, and did you check the bulb type (wattage) that is actually installed in the light sockets before wiring them up?

Go back and check all of your "hot" wiring (the B+ power supply wiring) to check for anywhere it might be shorting to ground. Also check the wiring inside the lights for insulation damage, or any damage to the bulb sockets that may create a short circuit.
 

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Discussion Starter · #4 ·
Do you have a diagram for the rocker switch? The relay looks right.

Here is a diagram for the OEM switch. I'm still digging......

I went straight to the relay from the battery (20 amp fuse) and used the "from 12v switched". (skipped the optional fuse panel connection)

Pin 3 is 12v in
Pin 4 is 12v out to relay
Pin 4 connected to pin 1 to turn on the LED indication switch is on
Pin 2 is ground for the ON LED
Pin 6 is from the dash light rheostat (dimming)
Pin 5 is ground or Pin 6 LED

I tied pin 2 and 5 (ground) together.

Relay:
12v from battery/20amp fuse to pin 30, Pin 87 to lights
Pin 85 to ground. Pin 86 from switch

View attachment 1142266
1142268


This is the guide I used when wiring the rocker switch. However I did not T tap pin 6 to pin 2. I kept pin 6 tapped into the cigarette lighter/12v positive wire so that the switch will illuminate only when the car is turned on.
 

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Discussion Starter · #5 ·
Your wiring sketch is correct, but you may not actually have wired it per your sketch. That fact that you blow 25A fuses instantly implies that you have a intermittent dead short somewhere, or that the bulbs installed in the lights draw significantly more than 25A.

Are these new or used lights, and did you check the bulb type (wattage) that is actually installed in the light sockets before wiring them up?

Go back and check all of your "hot" wiring (the B+ power supply wiring) to check for anywhere it might be shorting to ground. Also check the wiring inside the lights for insulation damage, or any damage to the bulb sockets that may create a short circuit.
Will do! Thank you both for the quick responses I will go check the hot connections right now.

As for the bulbs- I have not looked into what the wattage is. The previous owner installed the lights new but did not wire them up, hence why I am now taking on this project.

For the light damage, what should I be checking for specifically like would the wiring be blacked out or melted or something along those lines where an intermittent/dead short is created?
 

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You're looking for any type of insulation damage or exposed conductor that could short a 'hot' wire to ground. Aged, cracked insulation, insulation partially melted, insulation cut by contacting a sharp sheet-metal edge, etc.
 

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Discussion Starter · #7 ·
Your wiring sketch is correct, but you may not actually have wired it per your sketch. That fact that you blow 25A fuses instantly implies that you have a intermittent dead short somewhere, or that the bulbs installed in the lights draw significantly more than 25A.

Are these new or used lights, and did you check the bulb type (wattage) that is actually installed in the light sockets before wiring them up?

Go back and check all of your "hot" wiring (the B+ power supply wiring) to check for anywhere it might be shorting to ground. Also check the wiring inside the lights for insulation damage, or any damage to the bulb sockets that may create a short circuit.
The connections to power all still look solid however I noticed that the bulbs read 12v 55Watt on the back of the socket, does this affect the circuit more so than I realize? The connections to the light wiring looks good, the wires are all solid
You're looking for any type of insulation damage or exposed conductor that could short a 'hot' wire to ground. Aged, cracked insulation, insulation partially melted, insulation cut by contacting a sharp sheet-metal edge, etc.
As for damaged connections I did not see anything of the previous description. I did find that on the back of the bulb socket the lights are rated at 12v 55 Watts. What would I need to change to accommodate for this, if anything. Here are some more images incase my beginner eyes missed something...

(first image is driver side. Second image is passenger side. Third is my relay connections with inline fuse)
1142336
1142337
1142338
 

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The connections to power all still look solid however I noticed that the bulbs read 12v 55Watt on the back of the socket, does this affect the circuit more so than I realize? The connections to the light wiring looks good, the wires are all solid

As for damaged connections I did not see anything of the previous description. I did find that on the back of the bulb socket the lights are rated at 12v 55 Watts. What would I need to change to accommodate for this, if anything. Here are some more images incase my beginner eyes missed something...

(first image is driver side. Second image is passenger side. Third is my relay connections with inline fuse)
View attachment 1142336 View attachment 1142337 View attachment 1142338

55w at 13v would be about 4.25 watts per lamp. A 15amp fuse would be plenty for the two lights. Maybe even 10? (load + 20%)

Do you have a multimeter? Something to measure resistance?
 

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Discussion Starter · #11 ·
55w at 13v would be about 4.25 watts per lamp. A 15amp fuse would be plenty for the two lights. Maybe even 10? (load + 20%)

Do you have a multimeter? Something to measure resistance?
Right thats why I am confused as well, the lights used to work but suddenly decided not to. Anyways I do not have a multimeter on hand but If I can borrow one what would I be looking for?
 

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The fuse holder should be close to the battery. Remove the fuse.

It looks like you have connectors on the + wires at the lamps? I would disconnect both lamps there. The lamp resistance is very low when cold and about 2.5 ohms when hot (which is still low). We are dealing with cold. With the lamps out of the circuit we can check the rest of the wiring from the fuse holder to ground. No fuse in the holder.

With the lamp out of the circuit the resistance should be infinite (HIGH) digital meter would indicate OL. Analog meter would be all the way to the right. That would be with the relay triggered from the switch so the contacts would be closed. If there is a short the resistance will be very low. Could be a few ohms to zero. That is why the lamps are taken out of the circuit.

Measure from the end of the fuse holder that goes to the relay to ground. I'd use the battery minus (-) terminal/post

This will be a go/no go. OL no short, suspect the lamps/holders. Short you will need to isolate/check each section of the wire to ground.

If there is a low resistance you have a short between the fuse holder and the two lamp connectors. I would expect to see a short based on the blowing fuses.

I'd let @FJtest have a look at this first, he may have a better way to proceed. I know what I'd do but I'm not too good at explaining things.

Comments are welcome, anything to help @the_blue_berry out. I won't be offended :p
 

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The 55W rating molded into the sockets is just a MAXIMUM bulb power rating that the socket is designed to handle. It doesn't tell you anything about the bulbs that are actually installed in the sockets.

Did you pull the bulbs out of their sockets and determine what the actual bulb type or rating is? If 55W bulbs were actually installed they should only draw 4.2 amps each. The previous owner, in the never ending quest for 'more power', could have installed some other higher wattage bulbs.

Very rarely, and depending on the bulb's internal construction, a bulb can fail with an internal short if one of the filament support wires breaks, bounces around inside the bulb, and happens to short across the filament lead-in wires. If that occurs, the wire can 'spot-weld' itself across the lead-in wires and become a dead short.

Do this, in the following sequence:
1. Pull the bulbs out of their sockets, verify the bulb P/N and/or power rating, and confirm that the filaments and filament support wires inside the bulb (if used) are intact.
2. Visually examine the interior of the bulb sockets and make sure that the contacts are undamaged, and the insulating plastic supporting the contacts is intact.
3. Unplug the relay-controlled 'hot' wire to your lights from the relay's #87 terminal, and push a piece of insulated wire into the female Faston terminal. Momentarily touch the other end of the wire to the battery's + terminal; there should be a small spark and the lights should turn on. If they don't instantly turn on, and there is a larger spark or the wire instantly starts to heat up, then you have a short in the bulbs, the light sockets, or the wiring to the sockets.
4. If the lights DO turn on, and stay on, then you have a short somewhere else, in your relay or switch wiring.

(Lee44: Your multimeter-based troubleshooting guide is 100% correct, but the OP doesn't have his own digital multimeter, or know how to use one. Many digital multimeters have been blown up by someone accidentally getting the probes across some voltage source while they are in resistance-measuring mode. To help prevent a catastrophe with a borrowed meter, it may be better to try a very basic no-meter-required troubleshooting process first. This is a very, very simple circuit, and the fault should be pretty easy to locate.)
 

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FJtest said:
snip snip Many digital multimeters have been blown up by someone accidentally getting the probes across some voltage source while they are in resistance-measuring mode. To help prevent a catastrophe with a borrowed meter,
Unbelievable how easy it is to do that.... (don't ask) :)

@the_blue_berry Any progress on the issue?
 
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