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Volkswagen Passat CC - Number plate LED lights problem - Andrew7685

I recently bought a set of LED lights to improve the look of the car. I first bought a cheap pair from halfords and after fitting them they came on for 3 seconds then went off and didn't come on again until I switched the engine off and back on again then it does the same thing, on for 3 seconds then off?

After a quick look online I found out that I need ones with their own resistors and heat sinks built in. I went back to halfords and bought some more that had those specs, fitted these and yet again they came on and went off after about a minute, only this time they went off and never came back on. I presume they burnt out or something?

Can anyone figure out the problem or recommend a set of LEDs that work and if possible where I can get genuine OEM ones? Thanks.

Volkswagen Passat CC - Number plate LED lights problem - RobJP

Genuine ones ? A VW dealer.

However, I think you may be finding out that 'improving' the look of the car may have damaged something in the electronics. So it may end up costing you a fair bit to get it working 'as intended' again.

Simple lesson for the future : if it ain't broke, don't 'fix' or 'improve' it.

Volkswagen Passat CC - Number plate LED lights problem - elekie&a/c doctor
Lighting circuits in many modern cars are electronically controlled and load sensing.So if any non standard bulb is fitted,the system thinks this is a fault and shuts down the circuit.Hopefully,if you refit the original bulbs,then disconnect the battery for 5 mins,this will restore function
Volkswagen Passat CC - Number plate LED lights problem - gordonbennet

Do led lights improve a car's appearance, in the vast majority of cases they don't, there is nothing more crass than sticking latest bright bue tint fairy lights on a car where the rest of the lights are normal not as bright as true blue Daz white :-)

LED's can be useful as brighter replacements on things like reversing lights (where so many cars have only one) and as rear fog light bulbs if your car is prone to the red lenses bleaching in sunlight over time, but in sidelights and number plates, where the position colour and output don't suit the car and in some cases where number plate bulbs stick out of the holders and blind the driver following making the number plate almost impossible to read, which is possibly the reason for fitting them for many.

Thay also have to be fitted teh right way round or they won't work, and on a modern car will need ballasts built in to (hopefully) fool the cars electronics into not showing a bulb fault.

Edited by gordonbennet on 28/12/2016 at 09:28

Volkswagen Passat CC - Number plate LED lights problem - Bolt

You can get resistors to go with the led when you buy them usually, so it shouldn`t be a problem for the circuit once installed

as mentioned diodes only work one way round and flickering often occurs with poor solder joints inside light (had a few myself )

Volkswagen Passat CC - Number plate LED lights problem - Cris_on_the_gas

Car most likely to have a CANBUS system so you need to get replacement bulbs that are CANBUS compatible.

CANBUS using an electronic signal to control power to devices and the LED bulb uses much less current that a filament bulb.

might be easier just to stik the original back

Volkswagen Passat CC - Number plate LED lights problem - Bolt

Car most likely to have a CANBUS system so you need to get replacement bulbs that are CANBUS compatible.

CANBUS using an electronic signal to control power to devices and the LED bulb uses much less current that a filament bulb.

might be easier just to stik the original back

Thanks for correcting my mistake, my post refered to standard systems.

I should have said CANbus compatible led`s will do the job