Gilbert Han

Hi all!

I encountered a problem with direction indicator after I change DRL to LED light. It is DEPO brand. But I can confirm it's not a problem of LED itself.

Background: My car came from Canada, means low beam is always on. I think there was a little bit of mod on lighting wiring.

Symptom: When the engine is turned off, both direction indicator works fine. But as soon as I turn the engine on, it flashes really fast and right signal stop working.

Question: Is it a problem of light module? Is it possible to reset light program to get it back to stock? Or should I buy another light module? If it is not a problem of light module, what are possible causes?

Thanks!!

Petza914

These are front DRL bumper lights you're talking about or rear taillights as I wasn't aware that Depo made the front bumper lights. If it's the rear taillights, The bulb controllert in the car is likely not seeing enough resistance so it thinks the bulb is out (which is why it flashes fast) and then cuts the power to that circuit and probably displays an error message on the dash. You can try adding a resistor to that circuit, buy you probably need a new taillight. If you bought them used, this may be why the original owner sold them.

If it's the front lights, when you say flashes really fast then cuts off are you talking about the white fog light / drl circuit or the yellow turn signal. If it's the white light flashing, the car might have a current sensing DRL module installed that senses the change in battery voltage from when the car is off to when it's running and the alternator is putting out more voltage. If this has gone bad, it could be sending a bad signal to the lights.

Gilbert Han

Thank for your reply. That's really helpful.
What I mentioned above was fron DRL turn signal. It flashes really fast on the car dash with error message. And when I check it from outside, turn signal does not work.
Could you give me an advice how do I solve this problem?

Petza914

Do you have rear LED taillights too? In my experience, these are the ones that fail and then cause the signal on that side to shut down. You can try getting a resistor and introducing that into the turn signal circuit, but they get really hot and I don't like to use them. If you have rear LED lights and still have your original non-led (incandescent) versions, try and swap the led taillight on that side with the old one and see if things work normally again. If they don't and you also have the original front incandescent lights, do that swap too. This will help you to identify whether it's the front or rear led light that's causing the issue with the turn signal circuit. Once you've identified the bad light, you'll probably have to replace it.

Your car isn't a Turbo is it?

Gilbert Han

No, it's not Turbo.
I assume that it requres more current when engine is turned on, since low beam is always on.

And I don't have LED tail light, and I could identify front right LED light is somewhat problematic. Old incandescent light works fine.
However, I feel like problems lay on my car's side rather than light itself. When I swap left light to right, still right side is the problem, which light worked fine when it was on left side.

Petza914

Interesting that the problem stays on the right side of your car when changing the lights. With that info and that your OEM lights work fine, the car is not seeing enough resistance from the LED light and thinks the bulb is out.

You might want to buy a canbus compatible resistor pack and try plugging that in with the light to see if it resolves the issue.


These are closed up in boxes and won't get as hot externally as the open gold type, plus they can be ordered with a lot of different plug options where you might find one that's plug and play with your current light connector. If not, you'll just have to cut the plugs off and wire it in, but I'd test it with alligator clips or jumper wires before cutting anything or splicing it into your factory wiring.

Do you know if someone installed a current sensing DRL box on your car to make those LEDs come on with the ignition or does it look like the factory wiring going to the lights?

997_Toronto

Canadian Perspective: Having the headlights on as DRL is probably not contributing to the issue as that's a configuration available using the Durametric tool and does not require any wiring changes.

I updated my front DRL & taillights to LED. Everything worked fine for 6 months and then suddenly I started to face the same issue as you but with the taillight. I added a resistor to both taillights as per PETZA914's comment and the issue was resolved. Yes, it is weird that the lights worked perfectly for months and then out of the blue I started to see error messages on the dash. Follow PETZA914's instructions and use alligator clips to test the resistor before you start cutting wires. Once you know the resistor has resolved the issue, you can make the update permanent.

Gilbert Han

UPDATE:
I bought this one and tried to see if work fine.

But no luck on there. Lights are not working even when engine did not start, after I install those.

@PETZA914, And it looks factory wiring where turn signal bulb goes. but what is DRL box?

So I contacted to seller and he said that it works at the vehicles 13.75v minimum running power. Probably me next step would be testing voltage of my car. When engine is started voltage changes, may be this is why it's not working only when car engine is running.

If this is the case, what should I do to resolve this issue?
If I bought wrong resistor, let me know as well.