LED bulbs - would this work?

KekseKaempfer said:
Here you go. Relay internals look exactly the same as the A2's with the difference that the switch is attached to the front of the board.

http://www.audizine.com/forum/showt...d-turn-indicator-(hazard-switch)-mod-tutorial
Click to expand...

Hi Chris, since the article mentions the "bi-Metal" strip that is used in this modern flasher unit, does your promise "i'll do a Paddy Ashdown and eat my hat" still stand? (just kidding)

Perhaps someone can have a go at this and provide not only the opportunity for people to use LED bulbs, but also I am assuming that this would probably fix the relay when someone has broken it?

Steve B
 
I had to replace the flasher switch/relay of the beetle a while ago. I'm wondering if it is still in the garage. I wanted to open it up at the time and couldn't work out how to get into it. I'm in the garage tomorrow night searching...
 
Excellent find, Chris. :)

I'm away from home at the moment, and so I can't investigate further. Although, it looks like we may be one step closer to a solution.

Steve, have you managed to source LED bulbs for the indicators? If so, would you mind telling us details of them and what you think of them please?

Regards,

Matt.
 
Disappointingly I seem to have binned the old relay, which is completely out of character for me throwing anything away, So I can't investigate , even on a vw one. There was no guaranteeing it was going to be similar, but there was a chance.

Anyone got a duff one?

Chris
 
wilco184 said:
Excellent find, Chris. :)

I'm away from home at the moment, and so I can't investigate further. Although, it looks like we may be one step closer to a solution.

Steve, have you managed to source LED bulbs for the indicators? If so, would you mind telling us details of them and what you think of them please?

Regards,

Matt.
Click to expand...

Hi Matt,

That sounds great, if you plan on selling these please put me down for one!!!

As for the bulbs I have bought, it is difficult to comment on the performance, they were flashing so quickly (for obvious reasons) but the light was bright and strong and definitely yellow.

They even look like filament bulbs (similar to these in the picture below (but with the correct PIN offset) I bought them from EMTuning who have supplied most of my LED bulbs (can't remember the price, but they were around the same price as other sellers).

Steve B

Bulb.jpg
 
Spot on! Thanks Steve. :)

Good news.

I can confirm that the A2's flasher relay uses the U6043B IC. I will be trying this mod out tomorrow, and will report back with the results! :) Hopefully we may have sorted the indicators, at least.

Interestingly, my relay looked different internally to the pictured one from the A2OC. It has the same layout, but with different relays and slightly different positioning.

Regards,

Matt.
 
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Hi guys,

I might be out of subject here, but I found on eBay canbus error free LED indicator bulbs. Haven't bought them, just found them, but I have fitted 501 type LEDs to my A2 and they work just fine, no error given.

Regards,
Boris
 
67boris said:
Hi guys,

I might be out of subject here, but I found on eBay canbus error free LED indicator bulbs. Haven't bought them, just found them, but I have fitted 501 type LEDs to my A2 and they work just fine, no error given.

Regards,
Boris
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Hi Boris, unfortunately the LED indicator bulbs cannot be used without modifying your flasher control box. The reduction in current drain with the LED bulbs means the flashers act as if you have a bulb out and flash several times a second.

The above thread is discussing a way around the problem and it looks like we have an option. This will enable the LED bulbs that you mention to be used on our A2s.

No need to apologise though, this is an open and friendly forum and we appreciate all input that is well intentioned, so please keep it up, we all started somewhere.


By the way, the "bulb out" system does not check the sidelights, front and rear fogs and reversing lights, so you can use any LEDs on these error free or not.

You cannot use LED bulbs in the stop / tail lights because the error check would cause several error lights on your dash, because the system would "think" that your brake light switch has failed. The only way around that would be to fit two resistors on each stop/tail bulb, so 4 in total and that removed one of the main LED advatages, that of low current drain.

Steve B
 
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67boris said:
Hi guys,

I might be out of subject here, but I found on eBay canbus error free LED indicator bulbs. Haven't bought them, just found them, but I have fitted 501 type LEDs to my A2 and they work just fine, no error given.

Regards,
Boris
Click to expand...

Hi Boris,

Steve's correct in saying that the low current drain LED's cannot be used without modification to the flasher relay and that a way around this is to fit resistors across the bulbs to simulate a higher load. CAN-BUS friendly LED's are simply LED's with this resistor fitted internally; which, whilst it does work as you say, still has the disadvantage of high current drain. Thank you for your suggestion though, it's much appreciated. :)

Regards,

Matt.
 
Bad news unfortunately. The mod didn't work. :(

I tried the method in the link that Chris posted, but it does not work for our flasher relays. I got an extremely fast frequency; fast enough in fact that the relay could not even switch. I'm not sure what the problem is, I checked the pin out for the flasher relay on ElsaWin and it seems to be the same as for the A6 in the link, but it doesn't work.

The maths checks out as far as I'm aware; so I'm really not sure. Perhaps I can check ElsaWin again to confirm the flasher pins.

Regards,

Matt.
 
wilco184 said:
Hi Boris,

Steve's correct in saying that the low current drain LED's cannot be used without modification to the flasher relay and that a way around this is to fit resistors across the bulbs to simulate a higher load. CAN-BUS friendly LED's are simply LED's with this resistor fitted internally; which, whilst it does work as you say, still has the disadvantage of high current drain. Thank you for your suggestion though, it's much appreciated. :)

Regards,

Matt.
Click to expand...

Hi Matt,

Please correct me here because your electronics knowledge is FAR superior than mine. But the resistors needed to "fool" the bulb out warnings are unlikely to replicate exactly the same drain as a 21w bulb and so when it comes to indicators they would surely still flash too quickly? I think mine were "error free" but still flashed like there was a bulb out? So I think that you will not be able to buy any LED that will work with an unmodified flasher control box?

LED bulbs are expensive and so I wouldn't want anyone to think that "Error free" LEDs will work in the indicator circuit?

Steve B
 
Birchall said:
Hi Matt,

Please correct me here because your electronics knowledge is FAR superior than mine. But the resistors needed to "fool" the bulb out warnings are unlikely to replicate exactly the same drain as a 21w bulb and so when it comes to indicators they would surely still flash too quickly? I think mine were "error free" but still flashed like there was a bulb out? So I think that you will not be able to buy any LED that will work with an unmodified flasher control box?

LED bulbs are expensive and so I wouldn't want anyone to think that "Error free" LEDs will work in the indicator circuit?

Steve B
Click to expand...

Hi Steve,

You're correct in that the resistors are unlikely to match 21W exactly. The oscillation frequency is controlled by a combination of a resistor, capacitor and an integrated circuit inside the flasher relay. The hyper flash happens when the integrated circuit senses that sufficient load is not being pulled - this is 2.7A in our case. Assuming the IC is happy that 2.7A is being pulled, then it will use the OEM frequency. If it is not, the IC (U6043B) flashes at 2.2x the original frequency.

The method that Chris posted utilises changing the 2.7A cut off point, for a lower cut off such that LED's can be used. The actual load (the bulbs) does not decide the flash frequency.

Indeed, I can't recommend error free bulbs either, we need to have a setup that is confirmed as working before we recommend LED's. It's possible that the internal resistors may not meet the 2.7A; which I suspect is what happened in your case.

Edit: Theres a data sheet for the integrated circuit here, which explains it pretty well. http://www.mouser.com/ds/2/36/doc4726-29542.pdf

Regards,

Matt.
 
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wilco184 said:
Hi Steve,

You're correct in that the resistors are unlikely to match 21W exactly. The oscillation frequency is controlled by a combination of a resistor, capacitor and an integrated circuit inside the flasher relay. The hyper flash happens when the integrated circuit senses that sufficient load is not being pulled - this is 2.7A in our case. Assuming the IC is happy that 2.7A is being pulled, then it will use the OEM frequency. If it is not, the IC (U6043B) flashes at 2.2x the original frequency.

The method that Chris posted utilises changing the 2.7A cut off point, for a lower cut off such that LED's can be used. The actual load (the bulbs) does not decide the flash frequency.

Indeed, I can't recommend error free bulbs either, we need to have a setup that is confirmed as working before we recommend LED's. It's possible that the internal resistors may not meet the 2.7A; which I suspect is what happened in your case.

Edit: Theres a data sheet for the integrated circuit here, which explains it pretty well. http://www.mouser.com/ds/2/36/doc4726-29542.pdf

Regards,

Matt.
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The MORE I read on this forum, the more I realise that I don't know....I take my hat off to you for knowing this stuff:cool:
 
Hi Matt,

I there was an award for the best "clarity" of responses and the most helpful posts, you would have my vote on both counts.

The care you take over your answers (consistently) is obvious and much appreciated.

Thanks
Steve B
 
Many thanks, both of you. :)

My work involves a lot of stuff similar to this, hence, I try to help out whenever I can. It's good to hear it's of use.

I still can't work out why I was getting the rapid frequency. Using a 0.33 Ohm resistor, you should get a cut off point of 0.15A. I tried it with the filament bulbs still in, so I will have been well above this. I must have missed something. If anyone can help, that would be greatly appreciated. :)

Regards,

Matt.
 
wilco184 said:
Many thanks, both of you. :)

My work involves a lot of stuff similar to this, hence, I try to help out whenever I can. It's good to hear it's of use.

I still can't work out why I was getting the rapid frequency. Using a 0.33 Ohm resistor, you should get a cut off point of 0.15A. I tried it with the filament bulbs still in, so I will have been well above this. I must have missed something. If anyone can help, that would be greatly appreciated. :)

Regards,

Matt.
Click to expand...


I'm looking at the data sheet and wondering if you could just tie the threshold pin with a resistor, nullifying the bulb out circuit. In other words the bulb out circuit just wouldn't detect the removal of a bulb. It's a while since I did any electronics, I kind of gradually went off in to the world of software, so I'm a little rusty. I'd love to be able to devote time to this as you are. So any progress you make is greatly appreciated and you deserve the credit you are getting.

Chris
 
KekseKaempfer said:
I'm looking at the data sheet and wondering if you could just tie the threshold pin with a resistor, nullifying the bulb out circuit. In other words the bulb out circuit just wouldn't detect the removal of a bulb. It's a while since I did any electronics, I kind of gradually went off in to the world of software, so I'm a little rusty. I'd love to be able to devote time to this as you are. So any progress you make is greatly appreciated and you deserve the credit you are getting.

Chris
Click to expand...

Disabling the "bulb out" would not correct the problem of the quick flashing of the indicators, or the errors if you use LEDs for stop/tail bulbs.

But disabling the "Bulb out" is necessary when upgrading from non-DIS to DIS usually.

Steve B
 
Birchall said:
Disabling the "bulb out" would not correct the problem of the quick flashing of the indicators, or the errors if you use LEDs for stop/tail bulbs.

But disabling the "Bulb out" is necessary when upgrading from non-DIS to DIS usually.

Steve B
Click to expand...

I think you might be mistaking my use of 'bulb out' there. I'm specifically talking about the input to the comparator pin7 on the flasher IC.

Chris
 
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