LED DRL not turning on - only regular headlights. Planned by JLR?
It is a chip used to power the LEDs. Apparently it gets too hot and stops working. You can take it apart and replace the chip but the dealer will only replace the whole assembly. I have found a couple used assemblies on eBay and now have two spare headlights which I will replace the chips in. The chip is less than around $50 at powerfulUK. Avoid the Chinese ones, I tried that route and they lasted 3 months.
It is not a hard thing to do, I can swap one out in about 15-20 mins. PowerfulUK has a video on taking the front grill off which is basically all the work. It is a handful of screws and some clips to pop off.
I just replaced the chips on both my lights. The DRLs had been out for over a year. Now the DRLs and square lights next to them do work but they're not coming on when I have Auto selected. They'll come one when the headlights are on or I select the DRL setting on the ****. Anyone know what the cause could be?
Did a dealer code off your DRL’s while they were burned out? So you are saying when you’re driving around during the day (or night) and you have headlamps OFF or ON, the DRL’s are on. However if you are in Auto mode, the DRL’s are not on? That’s a weird one.
When my drivers side DRL burned out, I noticed in my IIDTool (code reading) that I had a code stored permanently for the problem - something about “fault to ground / voltage / issue drivers headlamp”. I cleared the code.
This is a long shot but maybe you need to clear the code. Long shot because, usually on modern LR’s if the problem is fixed, the stored code doesn’t continue to prevent the component from working. (unlike the old days where the code needed to be cleared to restore operation etc). So -- this is a long shot of a fix.
HCM-Headlamp Control Module 'A'
- Test Failed
- Test Failed This Monitoring Cycle
- Confirmed
- Test Failed Since Last Clear
When my drivers side DRL burned out, I noticed in my IIDTool (code reading) that I had a code stored permanently for the problem - something about “fault to ground / voltage / issue drivers headlamp”. I cleared the code.
This is a long shot but maybe you need to clear the code. Long shot because, usually on modern LR’s if the problem is fixed, the stored code doesn’t continue to prevent the component from working. (unlike the old days where the code needed to be cleared to restore operation etc). So -- this is a long shot of a fix.
HCM-Headlamp Control Module 'A'
- B10F3-11 (2E) Left front position light - circuit short to ground
- Test Failed This Monitoring Cycle
- Confirmed
- Test Failed Since Last Clear
- Test Failed
- Test Failed This Monitoring Cycle
- Confirmed
- Test Failed Since Last Clear
Last edited by nashvegas; Jan 21, 2026 at 08:16 AM.
It has resolved itself.
The behavior was, when it was off, DRL and lights were off. On auto, both things were off during daylight. On the DRL, the DRL would turn on, and on the low beam setting both the headlight and DRL would turn on.
Either the code resolved itself. Or after I finished with the headlights, I had applied rainx on the windshield and I never cleaned the windshield after application which you are supposed to do per the instruction on the bottle. Maybe that was blocking the ambient light sensor, not sure. So after I noticed they are not turning on on auto, I washed the windshield using the washer fluid and its working fine now.
We'll see how the $15 ebay boards I got hold up though. I just assumed they'd be coming from the same source as the powerfuluk guys supplier, but someone here has said there's lasted 3 months. The ebay boards didn't come with thermal paste but I added my own, hopefully that will help.
The behavior was, when it was off, DRL and lights were off. On auto, both things were off during daylight. On the DRL, the DRL would turn on, and on the low beam setting both the headlight and DRL would turn on.
Either the code resolved itself. Or after I finished with the headlights, I had applied rainx on the windshield and I never cleaned the windshield after application which you are supposed to do per the instruction on the bottle. Maybe that was blocking the ambient light sensor, not sure. So after I noticed they are not turning on on auto, I washed the windshield using the washer fluid and its working fine now.
We'll see how the $15 ebay boards I got hold up though. I just assumed they'd be coming from the same source as the powerfuluk guys supplier, but someone here has said there's lasted 3 months. The ebay boards didn't come with thermal paste but I added my own, hopefully that will help.
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