Curious issue with Osram headlights -- any electrical gurus?

[torga]

Unfortunately, my third-hand set of Osrams are immediately giving me issues. And it's a strange issue. I'm dead set on fixing these, because I think these headlights are worth the trouble.

When the car is running and the headlights are not on, the DRL lights work flawlessly. From the manual, it says the DRL are supposed to dim when the low beams get switched on. However, when I switch the low beams on, the passenger-side DRL simply shuts off (within 3 seconds) – the driver-side remains operational. The other LED light in the passenger-side housing also turns off when the low beams come on (the smaller, innermost light which is in the same spot as the stock high beam in the halogen housing). The low beams are unaffected by this DRL failure, the turn signals remain operational, and the high beams remain operational. When I switch the low beams off, the passenger side DRL turns back on like nothing happened. There is nothing wrong with the driver-side headlight.

And here's a kicker -- this is only an issue when the car is running.

When the engine is off and only the accessories/electrical systems are on, the headlights work flawlessly. Both DRL lights stay on when the low beams come on.

Since there is a voltage delivery difference between these two car states (~12.5V when the engine is off and ~14V when the engine is running), I’m curious if this signifies any failure from within the headlight, perhaps a loose connection somewhere or a faulty LED controller?

I've already checked simple things, such as fuses and loose headlight connectors. There doesn’t seem to be anything obviously wrong with the car-side connections. I also reached out to Osram to see if they've got any insights.

I do get a gauge cluster warning light when the DRL fails. It resets itself every time I turn off the car. These are the related codes I pulled:

• Light Switch (implausible signal), Code 02395
• Terminal 30 right (open circuit), Code 00927
• Terminal 30 left (open circuit), Code 01516
• Left low beam headlamp bulb (open circuit/short circuit to B+), Code 00978
• Left high beam headlamp bulb (open circuit/short circuit to B+), Code 01495
• Left DRL bulb (open circuit/short circuit to B+), Code 02745
• Right DRL bulb (open circuit/short circuit to B+), Code 02746
• Bulb for left front parking light (Faulty), Code 02394
• Bulb for right front parking light (short circuit to ground), Code 02395

 

[NewGuy1]

I would start by taking voltage measurements on all the headlight pins while cycling through the light switch and recording your voltages.
To help out a bit from my notes I believe these are the stock pins:
pin 4: DRL
pin 5: gnd
pin 6: Low
pin 8: high
pin 9: Turn
pin 10: parking

since it works when cars off my first thought is potentially loose wire/ bad ground that isnt seated properly and if affected by engine vibrations.

 

[torga]

This only started happening with the Osrams. I had the Helix lights installed before these which have a similar operation (DRL dim when low beams on) and they were fine. I'll still double check the pins to really cross this off the list.

I'm not entirely convinced that it's a loose wire because the DRL fails in the exact same way, after the exact same time (~3 seconds), every time. I feel like a loose wire would not be as predictable. Bad ground is definitely possible.

 

[NewGuy1]

This only started happening with the Osrams. I had the Helix lights installed before these which have a similar operation (DRL dim when low beams on) and they were fine. I'll still double check the pins to really cross this off the list.

I'm not entirely convinced that it's a loose wire because the DRL fails in the exact same way, after the exact same time (~3 seconds), every time. I feel like a loose wire would not be as predictable. Bad ground is definitely possible.

Its really just to start by eliminating the car completely first.
Without knowing exactly how these lights are made its hard to say its not a loose wire. (internal or external)
The headlights could sense fluctuation within the led output due to inconsistent voltage then shut off the DRL in response to try to minimize damage.
Which could be why it has a consistent "off" timing

For better or worse Osram headlights have much more going on than your typical chinese knock offs so it wouldnt surprise me.
I actually work in lighting and dealt with osram products before that had this type of response to inconsistent power being input, however that is dealing with commercial lighting and not auto but being under the same corp I would assume they share some technologies.

 

[torga]

Thanks for the insight! I'll hopefully have time to dive a little deeper tomorrow. Since the driver side is behaving, I'll check both connectors to compare voltages from each.

 

[smanierre]

Could it be a coding issue? I had to change my coding around to get all my lights to work how I wanted them. Could mess around with that to see if it changes anything. Also i'm having issues with mine that seem kinda similar. When I turn on my low beams with the ignition on, they turn on just fine. Once I start the car though, the driver will turn on for a few seconds then turn off. If I turn on my high beams, the drivers side will try to turn it on, usually by having it come on, shut off, then start flashing a bunch until it finally quits. Only when the car is running though, no issues when just the ignition is on so it doesn't seem to be the bulb or ballast.

 

[torga]

Could it be a coding issue? I had to change my coding around to get all my lights to work how I wanted them. Could mess around with that to see if it changes anything. Also i'm having issues with mine that seem kinda similar. When I turn on my low beams with the ignition on, they turn on just fine. Once I start the car though, the driver will turn on for a few seconds then turn off. If I turn on my high beams, the drivers side will try to turn it on, usually by having it come on, shut off, then start flashing a bunch until it finally quits. Only when the car is running though, no issues when just the ignition is on so it doesn't seem to be the bulb or ballast.

Totally possible it could be a coding thing. I did have to mess with the coding to get rid of the bulb out error after installing my Euro tails. But outside of that, I haven't changed a single thing about lighting-related coding. However, if it were a coding thing, I'd figure that both DRLs would be affected. Since it's just one, that's why I'm stuck on electrical/wiring issues.

We may have similar issues, just affecting different sub systems.

 

[GolNat]

Can you power them up on the bench? Remove the car from the situation.

Sounds like a possible grounding interference issue since it only happens when the engine is running.

 

[torga]

Can you power them up on the bench? Remove the car from the situation.

Sounds like a possible grounding interference issue since it only happens when the engine is running.

I don't have the equipment for that. If I can't figure this out with them on the car, I've got a buddy that can help me out with the bench stuff.

 

[brat_burner]

Totally possible it could be a coding thing. I did have to mess with the coding to get rid of the bulb out error after installing my Euro tails. But outside of that, I haven't changed a single thing about lighting-related coding. However, if it were a coding thing, I'd figure that both DRLs would be affected. Since it's just one, that's why I'm stuck on electrical/wiring issues.

We may have similar issues, just affecting different sub systems.

When I installed my Hella tails(factory bixenon headlamps), I was having issues with the parking lamp operation and left reverse lamp. When the cecm was coded properly for the tail lights, it switched function of two pins internally. I had to pull the connectors and swap two wires around to make it work again. Pretty sure Phur was the one that led me to the pin #'s.

 

[torga]

Interesting. I'll know more once I get a chance to confirm which pins are what, like NewGuy suggested.

 

[KollinWithaK]

Unfortunately, my third-hand set of Osrams are immediately giving me issues. And it's a strange issue. I'm dead set on fixing these, because I think these headlights are worth the trouble.

When the car is running and the headlights are not on, the DRL lights work flawlessly. From the manual, it says the DRL are supposed to dim when the low beams get switched on. However, when I switch the low beams on, the passenger-side DRL simply shuts off (within 3 seconds) – the driver-side remains operational. The other LED light in the passenger-side housing also turns off when the low beams come on (the smaller, innermost light which is in the same spot as the stock high beam in the halogen housing). The low beams are unaffected by this DRL failure, the turn signals remain operational, and the high beams remain operational. When I switch the low beams off, the passenger side DRL turns back on like nothing happened. There is nothing wrong with the driver-side headlight.

And here's a kicker -- this is only an issue when the car is running.

When the engine is off and only the accessories/electrical systems are on, the headlights work flawlessly. Both DRL lights stay on when the low beams come on.

Since there is a voltage delivery difference between these two car states (~12.5V when the engine is off and ~14V when the engine is running), I’m curious if this signifies any failure from within the headlight, perhaps a loose connection somewhere or a faulty LED controller?

I've already checked simple things, such as fuses and loose headlight connectors. There doesn’t seem to be anything obviously wrong with the car-side connections. I also reached out to Osram to see if they've got any insights.

I do get a gauge cluster warning light when the DRL fails. It resets itself every time I turn off the car. These are the related codes I pulled:

• Light Switch (implausible signal), Code 02395
• Terminal 30 right (open circuit), Code 00927
• Terminal 30 left (open circuit), Code 01516
• Left low beam headlamp bulb (open circuit/short circuit to B+), Code 00978
• Left high beam headlamp bulb (open circuit/short circuit to B+), Code 01495
• Left DRL bulb (open circuit/short circuit to B+), Code 02745
• Right DRL bulb (open circuit/short circuit to B+), Code 02746
• Bulb for left front parking light (Faulty), Code 02394
• Bulb for right front parking light (short circuit to ground), Code 02395

Could it be a coding issue? I had to change my coding around to get all my lights to work how I wanted them. Could mess around with that to see if it changes anything. Also i'm having issues with mine that seem kinda similar. When I turn on my low beams with the ignition on, they turn on just fine. Once I start the car though, the driver will turn on for a few seconds then turn off. If I turn on my high beams, the drivers side will try to turn it on, usually by having it come on, shut off, then start flashing a bunch until it finally quits. Only when the car is running though, no issues when just the ignition is on so it doesn't seem to be the bulb or ballast.

I didnt have Osram lights, but when I swapped to aftermarket headlights on my last Mk6, we had to do some coding changes to adjust the voltage going to the headlights because what was essentially happening is they were trying to draw too much off rip and essentially tripping themselves and shutting off. Was a similar issue where they would only last 3-5 seconds before shutting off. What we ended up doing was knocking the sent voltage to them down like .5v or something similar. Might not be the solution here but could be worth a shot.

 

[torga]

I didnt have Osram lights, but when I swapped to aftermarket headlights on my last Mk6, we had to do some coding changes to adjust the voltage going to the headlights because what was essentially happening is they were trying to draw too much off rip and essentially tripping themselves and shutting off. Was a similar issue where they would only last 3-5 seconds before shutting off. What we ended up doing was knocking the sent voltage to them down like .5v or something similar. Might not be the solution here but could be worth a shot.

Do you recall how you did that?

 

[Grabbit]

I don't know if the connectors are the same left to right but if so, could you remove the housings and swap them left to right to see if the issue follows the housing? That might help determine if the issue NewGuy1 mentioned is attributed to the OEM wiring up to the connector or something internal to the right Osram housing. Just a thought.

 

[torga]

Good thought, Grabbit. This is on my list of things to check if it comes to having to pull the headlights out again. As I'd be unable to get enough slack in the harness to be able to run the connectors to the opposite headlight with everything installed.

So far, I'm gonna be checking the few coding suggestions from this thread in the next couple days. If that doesn't pan out, I'll have time to uninstall things and go deeper next weekend.