blueplasticsoulman wrote:

Orangebean wrote:

EDIT- these look identical to the one's I bought. No guarantee of that though as they're from China...
http://www.ebay.co.uk/itm/a-pair-of-50W-4000LM-LED-headlight-Kit-H4-Hi-low-Beams-6000K-White-bulbs-L9V6-/263008237534?

So this replaces both high and low beam? In just 1 bulb?

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Can't say for the Chinese one- it just looks like the one's I bought
Just like the original H4 halogen with twin filaments, the one I have replicates that. Uses same hole and clip in back of reflector and plugs in to original loom H4 3 pin bulb plug, feeding the LED bulb via a black box.

Think I've seen the youtube video of the powerful UK install. Looks good.

gonna change all my lights for led if I can. Think you can get most of the interior ones in an led equivalent.

blueplasticsoulman wrote:

gonna change all my lights for led if I can. Think you can get most of the interior ones in an led equivalent.

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Do your research first- any bulb that is fed from BECM is more complicated than just plugging in any old 12v led bulb. The forums are full of tales of angst about tail lights, side lights, switch lights, indicators- the list goes on. I know Marty has done a lot of LED conversions.

reason I aint done it yet is cause I'm still info gathering. Read the blurb on paulp38.com. Tells you a few replacement bulbs but not all of them. As for headlights, what's the power rating supposed to be? The kit you have is 25w per bulb and an output of about 4000lumens per bulb? Is that insanely bright or is it just right? I hate them boy racers that have those piercing lights. Its like a laser pen in your rear-view mirror.

blueplasticsoulman wrote:

Is that insanely bright or is it just right? I hate them boy racers that have those piercing lights. Its like a laser pen in your rear-view mirror.

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For me the output is good.
Gilbertd said that as I was following him the other night...
"OB's headlights were a bright white but not dazzling in my mirror (so obviously set up properly)"

What made you buy them for £70 odd quid instead of cheaper normal h4 led's with an inline load resistor?

Performance, light scatter, BECM friendly, legality, MOT compliance.
All informed by user feedback on what a bad fit the normal (aka cheap) H4 LEDs is on the P38. I've got a conscience about the effect my lights may have on other road users. I want to improve my night vision, but not at the expense of screwing up everyone elses.

ok. Was just wondering if there was anything different about them.

Basically they'll be the same thing with a load resistor in, but they're of better quality and in a plug and play kit form?

Most of the LED headlamp kits don't need a load resistor - the LED chips are more powerful then standard single LED's so they draw a lot more current, and thus don't trip the headlamp warnings.

But the cheap LED kits are shite for beam pattern and cutoff. I've tried one and I couldn't get it anywhere near close enough to not be dazzling to other drivers.
the second set I bought from China direct are a lot better and might even be OK to use with the correct setting up, but out of the box as a 'plug and play' drop in replacement they were also still too dazzling to other drivers

current as in amps not wattage?

Yes - it's all related.

55w (std H4 halogen) at 12V is just over 4.5A

I think the BECM needs more than about 1A draw on the output for it to not think the lamp is blown - so anything more than about 12W (12v x 1A) should be fine.

If you work it out at 14v - which is charging voltage with engine running, then 55w/14V = 3.92A
Minimum would need to be about 14W.

Either way, it's not a problem with modern LED headlamp units, as they are all superbright or COB led chips, which draw a decent amount of power. I don't think I've even seen an H4 LED unit as low as 12/14w, so pretty much all of them should be able to run without triggering a warning.

but sidelights and indicators will need to be canbus compatible led's because of low power consumption?

For example, according to paulp38a.com this bulb should be right for sidelights

They should be OK, yes.

The lower wattage lamp circuits (reverse, tail lights, sidelights) need about 1.8W at 12V for them to not log an error.

ok. I did suspect all of this but thought it best to ask. No-one ever seems to post definitive answers on forums and people are sometimes left with only half a story. At least on this forum you get a straight answer.

Be good to cobble together an LED guide of what components fit where for anyone wanting to do it.

So far I've found this and this to be the most useful. But they're not complete.

Marty, have you confirmed the Wattage needed to satisfy the BeCM? I only ask as Dina's Merc complained about a blown front sidelight bulb. I didn't have any 5W capless bulbs but did have a couple of spare 3W P38 dash illumination capless bulbs so put one of them in instead. Bulb lit up nicely, and you couldn't see any difference between that one and the other side with a 5W in it, but the car still complained that the bulb was blown. Swapped it for a 5W and the car was happy again.

I can't comment on the Mercedes system, as maybe it does use actual CANBUS and does its error reporting differently.

But on the P38 the MOSFETS in the BECM have a 'status ' pin which will change state in various error conditions.

The under current warning on them is what triggers the P38 to think the lamp is blown. The smaller rated MOSFET will trigger the warning up to around 150-200mA, whereas the big ones, for the headlights, indicators, break lights, fog lights (front and rear) etc reckon in the datasheet they need at least 800-900mA of draw before it won't detect an error.

I seem to recall trying it on a rear one answer needing just over 1A before I could get it to turn off.

Makes no difference to me now... I've disabled the warnings on all but the headlights and front fogs at the moment as they're all still halogen incandescent lamps until I find suitable LED replacements and a place to set them up properly!!

I put led bulbs in my interior over a year ago, had no errors on dash, I found that footwell and puddle bulbs weren't very bright, so I changed them for slightly larger which meant removing the plastic covers, it seems that p38 Paul is having the same problem with the map reading as me, so I've left them alone, but they all work well.

Sorted.

Sidelights t10 Wedge 13smd

Headlights (look slightly yellow and a bit more fierce in the picture than they actually are. 6000k. 3800lumens per bulb. With adjustable beam)

Couldn't get a picture of main beam as it just blinds the camera. Very impressed though. Like driving home in daylight.

If you've got a friendly MoT test station, call in there and set them up on the beam tester. Assuming the ones you got are the same, or similar to those OB bought, they need to be properly alinged so they give the correct beam pattern. Bodywork looks shiny though.....

had it against the wall to begin with and think I got somewhere near with the roll off but I was planning on taking it round to my MOT man and seeing if he would check them out.

Car was cleaned yesterday. I do it once a week cause the sea air and sand don't keep it nice for long.