Register Login
The UK's No.1 Chrysler Owners Forum
Reply
 
Thread Tools
Old 26-08-2017   #16
Join Date: Mar 2011
Location: Berkshire, UK
Posts: 862
Thanks: 53
Trader Rating: 0
United Kingdom 
Re: Reversing Light is Pants....

That seems a very pragmatic course of action. We eagerly await your verdict when you've tested in the dark!
If the led is longer than the filament lamp, that could have a further positive effect by shining directly out of the "window".
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

TrevC is offline Reply With Quote Quote 
Old 27-08-2017   #17
Join Date: Dec 2006
Location: Southampton, Hampshire
Posts: 3,063
Thanks: 211
Trader Rating: 0
s130 has donated!
United Kingdom 
Re: Reversing Light is Pants....

Quote Originally Posted by TrevC View Post
If the led is longer than the filament lamp, that could have a further positive effect by shining directly out of the "window".
As far as the bulb length and position there is no "window". If you look through the reversing light "slit" then the bulb is located about 2 inches above the "slit". It has it's longitudinal upper half in a recess with reflective background. The recess is just long enough to accommodate this particular LED bulb. Longer ones will not fit.
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

s130 is offline Reply With Quote Quote 
Old 16-10-2017   #18
Join Date: Mar 2011
Location: Berkshire, UK
Posts: 862
Thanks: 53
Trader Rating: 0
United Kingdom 
Re: Reversing Light is Pants....

I was in Halfords today and in a "clearance" bin were a pair of 382 led lamps, without outer packaging, for 10. Naturally I snapped them up and I've fitted one to the reversing light. Certainly brighter, illuminates my car port better on this gloomy afternoon. I've yet to try it in proper dark, but it can only be an improvement. No errors displayed.
I'm resisting the temptation to try the other one as a DRL, rather keep everything else strictly legal. Having said that, I looked at a fully packaged 382 box, and although there was no E mark, there didn't seem to be any statement that they weren't road legal. Call me timid Trev, but I'm not going to chance it!
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

TrevC is offline Reply With Quote Quote 
Old 16-10-2017   #19
Join Date: Dec 2006
Location: Southampton, Hampshire
Posts: 3,063
Thanks: 211
Trader Rating: 0
s130 has donated!
United Kingdom 
Re: Reversing Light is Pants....

Quote Originally Posted by TrevC View Post
I looked at a fully packaged 382 box, and although there was no E mark, there didn't seem to be any statement that they weren't road legal. Call me timid Trev, but I'm not going to chance it!
On package and website actually says: "For interior and off road use only". (buried in the small print )
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides


Last edited by s130; 16-10-2017 at 17:59.
s130 is offline Reply With Quote Quote 
Old 16-10-2017   #20
Join Date: Mar 2011
Location: Berkshire, UK
Posts: 862
Thanks: 53
Trader Rating: 0
United Kingdom 
Re: Reversing Light is Pants....

Ah, that's what comes of me reading it quickly in the shop. Of course, the one I took home only had a hand scrawled label stuck on! Have you had a chance to try yours in the dark yet? As I said above, I'm not expecting it to be great, but any improvement has to be worth, in my case, a tenner.
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

TrevC is offline Reply With Quote Quote 
Old 16-10-2017   #21
Join Date: Sep 2017
Posts: 5
Thanks: 0
Trader Rating: 0
United Kingdom 
Question Re: Reversing Light is Pants....

Can the bulb in the reversing light even be described as illegal when its not part of the MOT ??
__________________
Lotty
LottyG is offline Reply With Quote Quote 
Old 4 Weeks Ago   #22
Join Date: Mar 2011
Location: Berkshire, UK
Posts: 862
Thanks: 53
Trader Rating: 0
United Kingdom 
Re: Reversing Light is Pants....

I just found this video, which explains potential problems with using leds in place of filament lamps:


The items in the video are much smaller than the P21W equivalent that I've used, so can't dissipate heat so well. I will, however, conduct some tests with the other Halfords lamp in the pack. I haven't got Big Clives thermal imager, and I don't want to trash the lamp, but I have a multimeter and I/R remote thermometer, so I'll report my findings when I've had a chance to play. Of course, in a reversing lamp application, there's not much time for the heat to build up anyway.
Likes twobigdogs liked this post
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

TrevC is offline Reply With Quote Quote 
Old 4 Weeks Ago   #23
Join Date: Dec 2006
Location: Southampton, Hampshire
Posts: 3,063
Thanks: 211
Trader Rating: 0
s130 has donated!
United Kingdom 
Re: Reversing Light is Pants....

Interesting article/information and for those small T10 bulbs (with load resistor) I would say (as a retired electronics engineer) basically factually accurate.

Some points to note.

1) Total heat dissipation of the LED bulb (with loading correction) vs normal bulbs will be nominally the same.

2) Bulbs dissipate their heat via the glass envelope (large surface area) and conduction through to the base connections. This means that hot spots are minimised

3) In the case of the T10 bulbs (with loading resistor) the wasted power has to be dissipated in and over a very small surfaced area component (the resistor) by radiation and thus the bulk of the heat will be conducted away via the circuit board tracks to the connection terminals.

4) With (3) in mind the P21W LEDs are a completely setup. First of all they have the traditional large bulb metal base through which loose heat through thus reducing hot contact spots. Secondly the Halfords ones in question have an upper body metal casing parts (ribbed = increased surface area) thus improving matters.

5) I'm not personally concerned about issues with the Halfords P21W LED bulbs especially when used in a reversing lamp.
Thanks Alanw47 thanked for this post
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

s130 is offline Reply With Quote Quote 
Old 4 Weeks Ago   #24
Join Date: Mar 2011
Location: Berkshire, UK
Posts: 862
Thanks: 53
Trader Rating: 0
United Kingdom 
Re: Reversing Light is Pants....

Agree with all your points S130. I've now performed some simple measurements on the Halfords led. I used my multimeter to measure the resistance across the terminals, and it read open circuit on all ranges, which suggests there is no load resistor across the input. I then measured the current at 12V, which was 0.36A, giving a power dissipation of 4.32W. The filament lamp came out at 21W, amazingly!
So, the led array has to get rid of, probably, about 5W under engine running conditions. Unfortunately I couldn't find my thermometer, but the metal case didn't get too warm after a couple of minutes, and as you said it is mildly finned. There appear to be 21 leds. If we assume they are arranged in groups of 3 in series, like the ones in the video, that would be 7 strings of leds each taking just over 50mA. This seems about right. Presumably a few hundred mA is enough that the bulb failure circuit doesn't trip, without the need for a resistor.
I wasn't prepared to take my lamp apart, but this seems to be a properly engineered unit. It's a shame that none of these lamps are type approved as in a P21W application they would be fine, provided they met the luminance requirement. I too am a retired engineer, please feel free to criticise the above!
Finally, you may well enjoy trawling Big Clives YouTube channel. I found his videos informative, amusing, and sometimes scary when you see what's available on line!
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

TrevC is offline Reply With Quote Quote 
Old 4 Weeks Ago   #25
Join Date: Feb 2017
Posts: 120
Thanks: 2
Trader Rating: 0
United Kingdom 
Re: Reversing Light is Pants....

I swapped out all the rear bulb's on the Stilo for Bosch's Pure Light bulbs and the difference is huge. A good cheap mod and everything is about twice as much light. If you have a Halfords trade card it's about 20 ish for the full set.
__________________
FIAT Forum Useful Links:
Donate to FF | Buy FF Merchandise | Classifieds | FF Insurance | How-to Guides

Yorkshire007 is offline Reply With Quote Quote 
Reply
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump
Similar Threads
Thread Thread Starter Forum Replies Last Post
(T) Reversing light activates with fog light Puntron Punto (Mk2/2b) 39 05-03-2017 11:36
(T) Rear fog light /reversing light problem seemore Ducato 26 26-06-2014 16:12
(S) Brand new in box fog light and reversing light - LEFT HAND DRIVE! silkblack Barchetta 10 09-12-2013 20:54
(T) Advice Trace Reversing Light Cable or Light for suitable connection murray670 Grande Punto 1 23-05-2012 23:04
(G) No reversing lights / abs light / warning light Scudo06 Scudo 0 23-12-2010 16:44