H4 DRL Bulb upgrade

I'm thinking of replacing all my front bulbs with led ones I'm assuming I'll need main beam, side lights, daytime running, indicators an high beam what codes do I need to replace them all please so I buy the correct ones some say H11 an some say other codes I need a full set any help appreciated
 
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In general, simply changing bulbs does not entail recoding.
Not strictly correct - there is lots of ‘bulb’ monitoring happening so that when a bulb blows you get a warning. The system is programmed to see certain resistances (of individual bulbs).

When you fit LEDs they have a different resistance so cause a bulb out warning - these are what need programming out (switched off).

That said, you can get CANBUS error free LED replacements which usually fool the vans monitoring system.
 
Not strictly correct - there is lots of ‘bulb’ monitoring happening so that when a bulb blows you get a warning. The system is programmed to see certain resistances (of individual bulbs).

When you fit LEDs they have a different resistance so cause a bulb out warning - these are what need programming out (switched off).

That said, you can get CANBUS error free LED replacements which usually fool the vans monitoring system.
I think I've misled people regarding codes I mean the codes to buy correct ones not error codes thanks tough mate I appreciate your help
 
I think I've misled people regarding codes I mean the codes to buy correct ones not error codes thanks tough mate I appreciate your help
Well that all depends on which headlight units you have
 
Ah ill just keep the yellow crap ones that are standard then I can't be bothered with it failing it's MOT everytime I take it in cheers for the help mate appreciate it
 
Ah ill just keep the yellow crap ones that are standard then I can't be bothered with it failing it's MOT everytime I take it in cheers for the help mate appreciate it
There are other legal brighter ones. Google white H4 lamps
 
H4 cheers are they the main beam ones are side lights,indicators,dlr and high beam on different codes or do they all come under the h4 code sorry if I'm being thick I'm just struggling to find what I need
 
The codes for the bulbs can be found in the picture above ;)
P21W
PY21W
W5W
H4
 
Good god I'm thick ok I've got it sorry about that I think joining this forum might be a mistake I've a thousand questions all probably very obvious I'm gonna start annoying people honestly I'm not usually this thick lol thank you everyone
joining the forum isn't a mistake, it's how you avoid making mistakes! Don't worry!
 
the search facility on the forum is very good - many topics have been covered already so spend a few minutes searching / looking first!

That said, dont be afraid to ask (some topics are 1000's of posts long and the info you want might be in one post!)

It is also one of the friendliest / helpful forums I frequent - must be something about bus owners ;)
 
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the search facility on the forum is very good - many topics have been covered already so spend a few minutes searching / looking first!

That said, dont be afraid to ask (some topics are 1000's of posts long and the info you want might be in one post!)

It is also one of the friendliest / helpful forums I frequent - must be something about bus owners ;)
Definitely helpful yeah your right I should probably do the search thing first it avoids wasting peoples time I'll bear that in mind cheers pal
 
Bumped my old H4 headlights a month ago, in favour of the H7s. Fitted Twenty20 DRL’s and it seems both have failed. Looks like I’ve now got to take the lights out again to replace them. Can anyone recommend some quality LEDs, that will last at least a bit longer. Such a pain this time of year to have to take the bumper off. I’m half tempted to just put standard bulbs back in.
 
Bumped my old H4 headlights a month ago, in favour of the H7s. Fitted Twenty20 DRL’s and it seems both have failed. Looks like I’ve now got to take the lights out again to replace them. Can anyone recommend some quality LEDs, that will last at least a bit longer. Such a pain this time of year to have to take the bumper off. I’m half tempted to just put standard bulbs back in.
What are the chances of both bulbs failing at the same time? I’d be looking somewhere else first. Wiring/fuses etc.
I’ve had those Twenty 20 fitted for quite a while no issues and I know a few other people on here use them also. No one has previously mentioned a failure as far as I’m aware.
 
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