Strange Sidelight problem on CLK230

[corpsup]

Hi. Recently I decided to put in LED bulbs in place of the normal bulbs in the two front sidelights. They worked fine but I got an orange warning light come up on the dashboard indicating a bulb was not working somewhere, but all lights were in fact working. I think the car didn,t like the LED bulbs so I put the old normal bulbs back, but neither left or right bulb would light up. The fuse is fine and when I put one of the LED bulbs back in it lights up fine, so there is power going to the light, but when I replace it again with the original bulb, again it does not lightup. I have read that the LED bulb might not be CANBUS. I don,t know what that means, but it seems the LED bulbs have upset the electrics somehow. Does anyone have any experience on this as I would like to get the original bulbs working and not use LED bulbs. Any advice gratefully received as I really can,t figure this out

 

[EmilysDad]

Ignition off, light switch off & then try them
I know that on my car, even when I replace a blown bulb with a known good bulb, the new bulb won't initially work .... I've to turn the lights off & then back on again.

 

[corpsup]

Thanks for your reply. I<ve done as you suggested, no luck. I,ve even disconnected and reconnected the battery but still the car seems not to recognise the original bulbs. They are type 435H6W. Wierd, I can,t figure it out at all.

 

[Blobcat]

Are the old bulbs still OK? They (unlikely) but could have been damaged on removal. I'd test them with a bit of wire and the battery to make sure they're good, if they are then you can take the fault finding to the next level which could be a session on Star diagnostics. But I'd be testing the old bulbs first to make sure they're still working. I'd also be getting a multi-meter onto the sockets to make sure they're getting power.

 

[corpsup]

Thanks. I actually bought new bulbs (type 435 H6W) from Halfords and they do not work either, but when I reconnect the LED bulbs they do. I,ts like the car does not see or recognise the original bulbs, only working with the LED ones. Very odd. Do you think a stars test would work it out?

 

[RUBBER_UNDIES]

You need a resistor on the led sidelights. Leds have a lot lower resistance to a normal bulb. The car senses This when it does a 'self check'

 

[Chrishazle]

You can buy canbus error free W5W LED easily. These have the resistor built in so the canbus does not see a lower current draw and think the bulb has blown. However, you may find a couple of other problems, as I did putting LED's into my S204 side and position lights on the front.
First, you have to check that the bulb works before putting the holder back in. If the bulb has sharp edges, it can catch as you try to pull the holder back out, dumping the bulb into the headlight - I could not retrieve it when it happened to me.
Second, I think the LED's fail early due to overheat. I finally used shrouded ones with no sharp edges, with a plastic lens on the front, when they failed the plastic lens was deformed presumably by heat.
I gave up and went back to standard W5W blue filament bulbs.