Hello, I recently realised that my number plate light has gone off, I can tell it got some water in. No problems! I thought, I'll replace it!

So I snap the light out and OMG that's a jaguar "special" light, let's find the part number and order it;

£50 shipping included for a number plate light?? Are you serious ?????? I found this insulting and disgusting. That's JLR giving us the finger.

So I thought I have nothing to lose, i'll try to repair it myself.

After removing the light, I heated it with wife's hairdryer a little bit, because I thought that the lens is fixed with silicone/windscreen like glue and heating it will get it soft.
But no! They are using superglue, black superglue! Superglue is good, but it degrades when it comes in touch with water. This light is designed to fail over time.
Even looking at the PCB design and resistor component values, they are using 30mah leds and they run them at 38mah. Common practice in the LED lighting industry to make sure the LEDs won't last forever.

So here is how to open it, just heat it up a little bit with wife's hairdryer, it helps even with superglue, just not that much. Then stick a small screw driver between the lens and the cover and turn it.
2 Things might happen. 1) the lens will break 2) the lens will make a slight "click" sound and separate from the housing. The second is mist likely as this glue is no stronger than my 98 years old grandma's teeth. Work your way around to do the rest of the lens and take it apart.



There are 2 clips inside that you have to push backwards to release the PCB, it's pretty obvious. Then you'll get to this:



Now notice a few things:
1) it looks like the water got in through the connector. That is NOT the case. As the water turns to vapour when the car is under the sun, it goes up. It then condensates again on the connector compartment and drips back inside, corroding your connector pins in the process. Smart design JLR. I really want to speak to two guys here. The systems engineer that wrote the requirements for this light, and the electronics engineer that came up with this solution to fulfil them. See what happens when "everything must be a black box in order to do proper engineering"? Yes, I am talking to you mate. Don't pretend that you don't understand.
2) It looks very dead, probably beyond any repair . Well, I've got good news, none of these components will die because of water, except the leds. Unless the corrosion has eaten through the PCB traces, replacing the leds will fix the issue.

So I got my wife's old toothbrush and my daughter's nail polish remover and cleaned the PCB. DON'T use nail polish remover to clean the lens. It will make it cloudy. Just a little bit of water and soap.

What happens is that those LEDs are not waterproof. Water will get in through their little lens and that corrodes something internally and makes the led a dead short in both directions.

Before removing the leds, take a picture and note where the little uneven corner of the led is, that's the GND side, and the other is the + side.

Bust out your old soldering iron and desolder the leds.
An easy way to do it is just put a little solder blob on the tip then stick it on the led side where the pins are slightly visible, don't feel bad for slightly melting the old led, it's gone anyway. Do one side of the led first, you'll notice that it started to move, use a pair of tweezers to slightly lift that side, then do the other side.

You don't want to pull hard, if it's not coming apart, you are doing it wrong. Go watch a few desoldering videos on youtube! You don't want to lift the PCB pad and damage it.

I used these leds for replacement:
https://www.ebay.co.uk/itm/262514721...r=561352088322

their colour and brightness looks exactly the same as the original, but even if they don't, you get 10 leds for £3, you can replace the other light too, and still have some left to fix 3 more lights!

I've asked the seller for the datasheet so we get a part number.

Now clean the tip of your soldering iron and sweep some of the old solder under the exposed pads. Make it quick, you don't want to overheat the board and damage it and it doesn't have to be squeaky clean, it's not an FQDN multipin IC, it's a 30mah LED, it will probably work for years even with a semi-dry joint. Don't overthink it because you will overdo it and make it worse!

Now the tricky part! Take your soldering iron and put some new solder on the pads, if you touch the iron tip on the pad first, then briefly touch the solder on the pad and then lift both the iron tip and the solder a little blob will stay on the pad. The whole process should take 2 seconds, don't leave the iron tip on the pad for more than that, it will damage the board.

Do this an all pads and make prepare to solder the new led.
Make sure that you solder it the correct way! GND of the new led must go where the GND was on the old led. 99% of the time, the little cut corner on the led marks which side is the GND so it won't be that hard to find!

With tweezers keep the led on the solder that you've added on the pads and briefly touch the tip of the iron on the led pins and the pcb pads. This should take less than 1 second and will melt the solder and you'll see that it has now slightly covert part of the led pin. That's enough! TIP, seconds before doing this clean the tip of your iron and apply a tiny bit of new solder, if it take you more than 10-20 seconds to touch the pin you need to clean the tip again and add new solder to the tip. Solder that stayed on the tip for too long has lost all it's flux and doesn't want to stick to anything, but for some out of this world reason it WILL stick to wherever it wasn't supposed to creating a short

Now do the other side of the led and finally the other led.

That's it! power it using a 12V power supply to make sure it works.


I left it powered for a few hours to make sure nothing overheats and by using an infrared camera I found out that max temp on the board is 40C now. Pretty normal.

Now assemble the PCB again. I used a toothpick to apply bathroom silicone as glue for the lens.

There you go! Take that JLR! Enjoy a beer or two and a double Angus beef cheeseburger with the £47 left.

Depending on your car the X351 LED license plate lights can be found all over Ebay for cheap? It turns out that since Jaguar was owned by Ford in the past they still use a ton of common Ford parts. So happens the license plate lights are one of those parts. I suggested this some time ago when I swapped mine out and was impressed how bright they were!

Several people got them but one did report that the later model XJ's had a different style of light? Maybe 2016 and up? Mine is a 2014 and had the sealed units.
Take a look but I believe these will replace the factory units? Less than $15 for the pair too!
LED Plate Lights
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Nope, the connector is different and unless you want to do some cable chopping they won't fit.

At least earlier (pre facelift) x351 have same register license plate light module than Focus, Kuga, Mondeo, S-Max... etc...
Bough pair for 15€ from my local autopart shop.
This one:

Yes I know, but 2016MY have their own specific connector. The fixtures look similar but you won't be able to plug it unless you chop the factory connector off.

Also, those ford lights are 5W while this one is only 0.7W.

Ok. Thanks for sharing.
Many people here thought it changed on facelift, but now we have fact.
I still believe its not JLR made, because Tata changed that in JLR when take over. Its not worth to desing an component, if similar part is available tested and sertified outside. (made by Tata itself?)

The ford ones are not 5 Watt. It is just a "box" for the standart bulb type what sits directly on the connector, It can be fitted with old style bulb or LED if wanted, as long the type is W5W .

Hello,

I believe this was done in an effort to reduce electronics consumption, eg when lights are on and motor is stopped because of start/stop system and traffic. 10w here, 20 there, it adds up. It very much looks like a JLR design. Tata introduced a system where everyone working there can file a new "patent" for a system, no matter how silly it is, as long as it's not dangerous.
If the "patent" was accepted the employee would get a small bonus eg £500. If the patent is used he/she would get eg £1500 for every model that will be applied.
This helped the company to stop paying payebt use fees to other companies, eg Ford, and also create a huge portfolio of it's own patents.
In this industry, it all boils down to patent ownership when it comes to assets.
But many seemingly great ideas made it to production that proved not so good over time.
This is why JLR is uniquely strange and uniquely stupid sometimes, but always unique.

Now this light design might well be someone else's design, but it passed JLR validation. Someone looked at it and said "yeap, sounds like a great idea for a 99% profit margin."

Absolutely. The power saving started already well before Start and Stop systems because alternator load is increasing consumption = CO2.
Nobody found eletric power steering anyhow better than traditional belt driven pump, but still we have them in new vehicles because again one way to reduct consumption.
My bet are that this light module is just purchased somewhere outside by lowest bid wins. There are plenty of manufactures far east making these kind of modules for less than 1USD on volumes fror different vehicle / machinery manufacturers, so its no worth to spend any desing hours...

Great write-up. Many thanks.

I was fortunate as I have an early X250, so cheap replacements were everywhere when one of mine went.

Correct. That's what I posted? 2016 and up have changed the setup and they don't swap anymore. But the earlier cars it's a simple 5 minute swap because of the Ford parts connection as Vasara posted above.
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