DRL issues

[Phil21185]

Ok, so my cheapy Chinese DRLs have been on for over 6 months in all weathers and conditions and have worked great (for the price I'm pleased anyway)

Last night my neighbour knocks on to say my lights are still on on the car.  I have a look and its the DRLs.  I know that after switching the car off they stayed on for a little while but then usually go off completely after a bit.  The driver side one has always been brighter than the passenger side when this happens as well but I've never thought anything of it really.

However, the car has been stood for several hours by this point and they are still on.

I can only pinpoint this change to the same time as hardwiring my dashcam.  I got a generic £13 kit from amazon which is supposed to sense the car's battery voltage and shut off if it is less than about 11.7v I think.  So I put the fuse tap into F73 in the passenger footwell, which is a constant live supply to the auxiliary alarm.

Thinking this was causing the DRLs to stay on; as there is a constant draw on the battery, maybe the car's electrics stayed on longer than usual, allowing a seepage of power to the DRLs - I moved the dashcam to fuse 86.  Same problem.  I've noticed tonight that the DRL's are still on to the extent that they were for a few minutes after switching the engine off.

I've just been out and unplugged the cam for now to see if that cures the problem but has anyone else had this?

They're the 'fang' style DRLs in the grille sails with a conrtol box and 3rd dimming wire.  @kpg has some, I know and IIRC @Victory or @vibeone have them too?

Any similar issues with yours, guys?

[kpg]

Hmm that's a worry. An old set I had used to stay on after the car was turned off, but we're very very dim. This is a worry if the dashcam wiring is causing the issue. I haven't hardwired my cam in yet so I'm not sure if this happens mine. What I will say is that my previous set would never stay on with the 'guide-me-home' function but this newer set does ? And it's wired in exactly the same way.

If it's not the wiring it could be a defective set of drls. I'm sure the quality consistency wouldn't be too good on these based on my experiences with 3 sets.

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[Phil21185]

Did you buy all yours from the same place?  Mine are still on, so I don't think its the dashcam doing it, unless that has tripped something to make this happen and it will continue to do so...

When they are supposed to be on, they work fine and dim as they should with the lights on, but as I say, the past couple of days (though it could be longer and I've not noticed) they seem to be just on dimly (though the drivers side is noticeably brighter) after then engine is off...

EDIT:  Could it be a bad earth maybe?  Its grounded to the common battery ground point (so I suppose, it is wired to the battery...)  Positive is fuse tapped to F42 in the engine bay...

[kpg]

Did you buy all yours from the same place?  Mine are still on, so I don't think its the dashcam doing it, unless that has tripped something to make this happen and it will continue to do so...
When they are supposed to be on, they work fine and dim as they should with the lights on, but as I say, the past couple of days (though it could be longer and I've not noticed) they seem to be just on dimly (though the drivers side is noticeably brighter) after then engine is off...

I got my first set from a different place than the other 2. The first set were rubbish and the second set only died when water got in during the bad flooding.

Have you checked the wiring in the engine bay ? Is the connection to the battery secure ? Sounds like it's getting a constant feed. I'll try and trace my wiring at the weekend and you can compare.

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[Phil21185]

Thanks bud.

As I say, they've been like this since new, but always have gone off completely after a few mins.

I seem to remember that part of the ECU sort of 'shuts down' all power after a certain amount of time and i wondered if something I'd done recently was preventing it from now doing so...

Edit: just had a thought. I'm pretty sure they don't do this in the day- they'd be bright enough to see - so either it's due to my auto lights or due to the fact that the DRLs are at 50% brightness when I switch off the car. If the part of the controller circuit which dims them when the headlights are on is capacitive could it be storing enough juice to feed the DRLs for a while after engine off...?

I shall experiment tomorrow.

Another edit: no I shan't, I shall go out in my pyjamas and experiment now!

[Phil21185]

I am now cold and wet but my DRLs are off.

Looks like I'm on the right track. I just cycled the ignition but made sure that my headlights were off before turning the ignition off again. DRLs were at full brightness and went off completely when I switched the car off.

Wonder if this means the dimming circuit is failing? Have to test that in drier weather!

[Jonro2009]

I am now cold and wet but my DRLs are off.
Looks like I'm on the right track. I just cycled the ignition but made sure that my headlights were off before turning the ignition off again. DRLs were at full brightness and went off completely when I switched the car off.
Wonder if this means the dimming circuit is failing? Have to test that in drier weather!

Good fault finding skills there! You’re closer to finding the problem now, I was going to suggest a bad Earth but that doesn’t sound as likely now, still worth checking the wiring from one end to the other. Can you disconnect the dimming wire and see if the problem remains? I rarely use the parking/side lights independently it’s either dipped beam or off. If you are like me you could wire the dimming wire to the dipped circuit and see if that throws up the same behaviour?


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[Phil21185]

Hey Jonro nice to see you again.

That would have been my next thought, except that the dimming wire is already wired to dipped beam. Same principle applies though.

I imagine the cheap Chinese circuit has a relay to a resisted circuit when voltage or current is detected on the dimming wire. When I switch the car off with the auto headlights on (which I tend to leave on all the time) the "dimmed" circuit must still be open (I mean closed =]) and whatever method of resistance employed is probably eeking out some volts until empty. I don't think it's drawing from the battery as F42 is switched live so nothing available there when engine off.

I'm not too clever with my in depth electronics but it strikes me that a similar circuit could be a achieved with a couple of transistors and a resistor or two. 

[drsdriver]

This is why I avoided buying the cheap Chinese lights when I had my Mk3 Titanium . I paid out for the Ford Nolden ones and I never had any issues with them in over 4 years. Px’d the car now, and the Ford salesman liked the drls, as they are not very common. 

Hope you fix your problem. 

[Phil21185]

Thanks Graham, but the maths is not convincing:

My set, £30.  Nolden ones £240.

My set, 6 months.  Your set, 4 years.

Price equates, but I'd rather replace if and when I have to!

Plus I prefer the look of the fangs ones.

 

well actually I prefer PFLs in the headlights, but they are £600.....

[Phil21185]

Some more experimenting:

Turning off the engine with the headlights on (so DRLs dimmed) means they stay on as I've described. If I then turn the light switch on the car to a position where the DRLs aren't dimmed (so either off or sidelight), even with the car still off, the DRLs go off.

So is the control box leaking power from the dimming wire input to the DRLs themselves? I wonder if I switch the guide me home headlights off, the DRLs will go off when the light switch is left on anyway?

[drsdriver]

4 hours ago, Phil21185 said:

Thanks Graham, but the maths is not convincing:

My set, £30.  Nolden ones £240.

My set, 6 months.  Your set, 4 years.

Price equates, but I'd rather replace if and when I have to!

Plus I prefer the look of the fangs ones.

 

well actually I prefer PFLs in the headlights, but they are £600.....

Yours might be cheaper, but time is also money spent trying to fix it , if you can’t fix it then more time rebuying and refitting the new ones. 

But it’s down to choice on  what you prefer . 

[Phil21185]

Well part of the fun is finding out what's wrong and fixing it and to be brutally honest, it's the reason I'm pretty capable at a lot of different things.

Compared to friends of mine who can't wire a plug or get halfwords to change their wipers for them and be robbed for the privilege...

Update on the issue is that I think it IS guide me home related.

Pulled up tonight having had auto lights on and sure enough, DRLs were dimly lit. Switched the light switch to off, DRLs went off. Switched back through sidelight setting, no DRLs. Dipped beam and auto, dim DRLs but interesting to note that the dipped lights didn't come back on as per guide me home. All done with the ignition off.

Next test tomorrow as I didn't have time today is to turn the guide me home setting off on the dash.

Still doesn't explain why DRLs don't go completely off after GMH lights time out...

[Jonro2009]

It’s got me baffled pal, it makes no real sense but it seems to be quite specific in behaviour. It seems like there is some current leak somewhere allowing the lights to illuminate.
It’s late and I’m tired so forgive me if you’ve answered this already. Where are you getting your live feed from? Is there any occasion where your engine is running and your DRLs are off?

I’ve been pretty busy recently, hence my ‘quiet’ spell. My wee girl hasn’t been well, in and out of hospital but on the mend now so that’s where my time is spent mostly. And like most men I can’t multi task so if I’m on baby sitting duty (which my wife insists on calling ‘parenting’) then I don’t tend to get much else done. I don’t like to sit behind my phone or iPad when Freya is with me as it’s a ‘blink and you’ll miss it’ time of her life, my wife on the other hand can do both and even find time to tell me what I’m doing wrong all at the same time lol.


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[madmole]

I went for the Noldens which I got for £100 faultless for 4 years, and fantastic looking

However whats gone on your Chinese ones is an internal diode. So they are now allowing current across the dip beam circuit if the lights are on when switched off so the sensor wire is no longer pulled to 0 volts and switching them off. Compounded by the fact that the cheap ones assume the focus is a normal 12v DC system, when in fact its a PCM 12v system (so not a constant 12v when running, which buggers electrics not designed for a PCM waveform and wears out the diodes as they are constantly being hit by pulses

 

Best bet is to buy a cheap £5 DRL controller and wire the LEDS directly using that to bypass the original broken controller

[Phil21185]

14 hours ago, Jonro2009 said:

It’s got me baffled pal, it makes no real sense but it seems to be quite specific in behaviour. It seems like there is some current leak somewhere allowing the lights to illuminate.
It’s late and I’m tired so forgive me if you’ve answered this already. Where are you getting your live feed from? Is there any occasion where your engine is running and your DRLs are off?

I’ve been pretty busy recently, hence my ‘quiet’ spell. My wee girl hasn’t been well, in and out of hospital but on the mend now so that’s where my time is spent mostly. And like most men I can’t multi task so if I’m on baby sitting duty (which my wife insists on calling ‘parenting’) then I don’t tend to get much else done. I don’t like to sit behind my phone or iPad when Freya is with me as it’s a ‘blink and you’ll miss it’ time of her life, my wife on the other hand can do both and even find time to tell me what I’m doing wrong all at the same time lol.


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I'm in exactly the same boat mate to be honest. James had bad reaction to rotavirus jab (technically an oral gel but nvm) and been pretty absent myself. The best part is that when I do exactly as my wife does in certain situations and things still don't work out (eg the sleep routine frequently ends with her reading a book with James dozing quietly, or just as frequently ends with me holding a screaming baby who will NOT be out down!), it's still my fault!

DRLs are fuse tapped into F42, black to main negative terminal in engine bay (effectively direct to battery) and dimming wire scotchlocked to passenger headlight wire.

4 hours ago, madmole said:

I went for the Noldens which I got for £100 faultless for 4 years, and fantastic looking

However whats gone on your Chinese ones is an internal diode. So they are now allowing current across the dip beam circuit if the lights are on when switched off so the sensor wire is no longer pulled to 0 volts and switching them off. Compounded by the fact that the cheap ones assume the focus is a normal 12v DC system, when in fact its a PCM 12v system (so not a constant 12v when running, which buggers electrics not designed for a PCW waveform and wears out the diodes as they are constantly being hit by pulses

 

Best bet is to buy a cheap £5 DRL controller and wire the LEDS directly using that to bypass the original broken controller

You know when I said I don't know much about electronics... I understood 'diode' and 'volts'!

But I get the gist. Cheap box knackered.

Even writing this I thought about attaching the dimming wire to the return side of the headlight bulb to reduce the chance of any stray current but then, if there was any power getting to that wire, the headlights would surely be illuminated too? Ah wait, they take a lot more power to illuminate than the DRLs of course...

Next step just to confirm would be to disconnect the dimming wire and run through as I did above. 

I'm pretty handy with a soldering iron (even surface mount stuff) so I suppose I couldn't replace the diode in question?

 

Edit:: oh wait you mean PWM? Well I could make a new one with a 555 and a MOSFET surely?

[madmole]

Disconnecting the dimming wire would be a good test. If that works then options would be solder a new Diode into the dimming wire or stick an extra resistor on it to pull it down to 0V

[Phil21185]

When I have half an hour on a dry day I'll test, rip them out and do that!

Next mod I want to do after bonnet lifters is one of yours, Stephen - heated seats! Dug out your tutorial from a while ago and fancy it!

[madmole]

Well worth the effort, though you should have done it 2 months ago!

[Phil21185]

I know :(

My indecisiveness stems from the fact that I've seen a set with nice looking chrome rotary switches a la the climate dials in my car, and would look great just either side of the standard 12v socket bit.

2 problems, one the kit is £70 instead of £30 and two, the more I look, the more I think the drivers side one would foul the Z handbrake when applied (which will give you an idea of where I want to site them)

So if it's back to on the seat valance, I want some flush rotary switches that can't be knocked as you get in and out. They're still £60 a set. So it's a next month job. Just as the weather warms up...