Intermittent headlight problem

[AugyIA]

My son's 2014 FR-S has a headlight that is working intermittently. The passenger headlight will come on almost always but after driving it will go out occasionally. The driver side has no issues. I'm not super familiar with the variety of headlights and this car was purchased used with a replacement bumper (believe it is a BRZ bumper). The headlights have the up/down adjustment dial on the dash which works. Other than that, I don't know much about the headlights.

I did a quick look at the connectors and what wiring I could see but nothing jumped out at me. Any suggestions on where to look or how to diagnose?

Thanks for any help.

[Drifter X]

Originally Posted by AugyIA

My son's 2014 FR-S has a headlight that is working intermittently. The passenger headlight will come on almost always but after driving it will go out occasionally. The driver side has no issues. I'm not super familiar with the variety of headlights and this car was purchased used with a replacement bumper (believe it is a BRZ bumper). The headlights have the up/down adjustment dial on the dash which works. Other than that, I don't know much about the headlights.

I did a quick look at the connectors and what wiring I could see but nothing jumped out at me. Any suggestions on where to look or how to diagnose?

Thanks for any help.

Can we get a pic of the headlights on? I want to see the color they are. The color will kinda give me a hint to whether you have halogen bulbs or a HID or LED system?


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[BigTuna]

It looks like it's got an FRS bumper, with BRZ headlights. I'd double check the connections to make sure there isn't anything loose.

Maybe this will help is looking for the connections that could be lose.

[AugyIA]

Originally Posted by Drifter X

Can we get a pic of the headlights on? I want to see the color they are. The color will kinda give me a hint to whether you have halogen bulbs or a HID or LED system?


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He's out at the moment but when he gets home I'll take a picture and post. Thanks!

[AugyIA]

Originally Posted by BigTuna

It looks like it's got an FRS bumper, with BRZ headlights. I'd double check the connections to make sure there isn't anything loose.

Maybe this will help is looking for the connections that could be lose.

Thanks for the clarification and the link to the video. I'll have some time over the next few days and can dig a little deeper. It does seem likely that a poor connection could be introduced if the previous owner did that headlight swap.

Now I'm curious why change them but will do some googling...I suppose the BRZ "looks better" or has the aiming function whereas the FRS did not or something along those lines.

Thanks again...great help and much appreciated!

[AugyIA]

Good info here on the differences...more for my education but someone may stumble across this later :-)

https://www.perrin.com/blog/post/brz...beam%20lights.

[YamahaR86]

Originally Posted by AugyIA

Thanks for the clarification and the link to the video. I'll have some time over the next few days and can dig a little deeper. It does seem likely that a poor connection could be introduced if the previous owner did that headlight swap.

Now I'm curious why change them but will do some googling...I suppose the BRZ "looks better" or has the aiming function whereas the FRS did not or something along those lines.

Thanks again...great help and much appreciated!

FR-S was cheaper of the twins until they came out with the Release Series and transferred over to Toyota where more premium stuff was added standard.


One thing was the BRZ had "boomerang" lights. The FR-S was barebones minimum, a bulb and reflector housing. The BRZ might have been LED included headlights.

[AugyIA]

Ok, did a lot of googling today...not sure I'm smarter or not but read a bunch of stuff about headlights.

The car is a Monogram model...with BRZ headlights. The boomerang LED doesn't light up...that led me down a several hour rabbit hole of reading.

I have bookmarked a bunch of links and will try to figure out what the previous owner did while trying to sort out the intermittent headlight issue. I was concerned it was going to be some sort of cobbled-together mess with tape and wire nuts and taps. I was relieved to find it all looks like factory wiring for the most part. However, I noticed a yellow wire on the back of the LH harness (from the headlamp assembly) that was cut and not connected to anything. I suspect that runs the DRL or indicator but didn't see a yellow wire on any wiring diagrams.

I plan to do a full accounting of the wiring with pen and paper tomorrow and try to figure out what I have. From there, I hope to sort it all out. My son would really like to have the boomerang LED's work...seems like something I'd want too...just not sure if it is as easy as re-pinning things or if I need to introduce diodes or remove resistors (things I read about during my google searches today).

Once I have a better idea of what I'm dealing with I might have an intelligent question or two... :-)

[soundman98]

those housings are 'xenon'(oem term) or 'hid' (aftermarket term)

given the age of the car, my first guess is that the bulbs are going bad. iirc, they should be d4s bulbs. if you take one out and look at the little capsule inside, if it's almost entirely black, it's a good first step(they start clear, and then slowly get blacker as time goes on)

the fact that the height adjuster in the car works tells me that the previous owner spent time doing it right, though the boomerang not working is suspect...

[AugyIA]

Originally Posted by soundman98

those housings are 'xenon'(oem term) or 'hid' (aftermarket term)

given the age of the car, my first guess is that the bulbs are going bad. iirc, they should be d4s bulbs. if you take one out and look at the little capsule inside, if it's almost entirely black, it's a good first step(they start clear, and then slowly get blacker as time goes on)

the fact that the height adjuster in the car works tells me that the previous owner spent time doing it right, though the boomerang not working is suspect...

Thanks. I will pull the bulbs and look at them. If nothing is obvious I assume I could swap them left to right and see if the problem follows the bulb, correct?

Also, doing a little more reading, it sounds like there was a resistor on the FRS that has to be removed or it can damage the BRZ DRL LED's. I will look for that resistor when I get into it but am wondering if the boomerang LED's can be bench tested? Could I pull the headlamp assembly off the car and connect the proper + and ground wires to a 12V supply to verify they are still functional? Not sure which wire(s) but assume I can find on a wiring diagram somewhere. Just not that familiar with LED's and if they run off standard 12V supply.

[AugyIA]

I swapped bulbs and will let him drive it and see if the issue follows the bulb. Should know later today.

While in there, I documented the wiring and will do some research. I don't know where the "resistor" is or was so I wasn't able to confirm if it's been removed.

Main question I have right now is where to find a wiring diagram for the headlight harness. The car is a Monogram model and the headlight connector is 8 pins (2 unused). This is different from any FRS wiring diagram I can find (they are all 6 pin connectors) so I assume the Monogram is slightly different from a typical FRS.

[Tcoat]

Originally Posted by AugyIA

I swapped bulbs and will let him drive it and see if the issue follows the bulb. Should know later today.

While in there, I documented the wiring and will do some research. I don't know where the "resistor" is or was so I wasn't able to confirm if it's been removed.

Main question I have right now is where to find a wiring diagram for the headlight harness. The car is a Monogram model and the headlight connector is 8 pins (2 unused). This is different from any FRS wiring diagram I can find (they are all 6 pin connectors) so I assume the Monogram is slightly different from a typical FRS.

The Monograms came with the same lights as the BRZ not the FRZ so that is where everybody is confused. I did think it was odd that somebody would swap BRZ lights and go to the massive amount of work needed to get the adjusters too work!


Here are the wiring diagrams. Should be in the 2014 one.
https://demos.starbase7.net/t3Portal/

[AugyIA]

Originally Posted by Tcoat

The Monograms came with the same lights as the BRZ not the FRZ so that is where everybody is confused. I did think it was odd that somebody would swap BRZ lights and go to the massive amount of work needed to get the adjusters too work!


Here are the wiring diagrams. Should be in the 2014 one.
https://demos.starbase7.net/t3Portal/

Thanks, that clears up a lot. I do think, though, the headlight assemblies are BRZ and not FRS Monogram after looking at pictures. I wonder if the Monograms were replaced after damage or something? Maybe it was cheaper to do or the Monograms were unavailable?

Assuming that he does have the BRZ assembly, I'll have to review the wiring and try to figure out if the LED boomerang is being powered and/or why it's not working.

Here is picture of his headlight:


This is what I found online as what I believe would be an FRS Monogram:

[Tcoat]

Originally Posted by AugyIA

Thanks, that clears up a lot. I do think, though, the headlight assemblies are BRZ and not FRS Monogram after looking at pictures. I wonder if the Monograms were replaced after damage or something? Maybe it was cheaper to do or the Monograms were unavailable?

Assuming that he does have the BRZ assembly, I'll have to review the wiring and try to figure out if the LED boomerang is being powered and/or why it's not working.

Here is picture of his headlight:


This is what I found online as what I believe would be an FRS Monogram:

Unfortunately I can't see the pics since they are blocked at work so can't help beyond that monogram used different headlights. They could also be after market? Anybody that can see them?