Hi @donfurlan ,

Here’s some images taken from the schematics for the motherboard.

First check if there is power on the eDP connector pins 21-22-23. This is the VIBL12 power supply for the backlights.

If there is no power there then check the input pin 5 of U9. If not there check resistor R361.

If there is power on the eDP pins then you may have to check the backlight enable circuit as there is always backlight power to the panel but it is turned on and off in the panel by a signal on the Backlight ON lead connected to pin 25.

The lid sensor is just one component that can turn the backlights on or off by sending a signal to the motherboard chipset which then places or removes a signal voltage on the Backlight On lead

(click on images to enlarge).

Hopefully a start

Hi @donfurlan ,

It seems as though the power to the backlights is there all the time but relies on the lid switch telling the chipset that the lid is open so turn on the power to the lights.

I can’t see it from your image but the lid switch is connected to pin 6 of JBTN1 (power button board) connector so presumably when the lid is closed it appears that either a voltage signal which is on pin 5 is connected to pin 6 or perhaps an earth from pin 7. It could also be that the voltage signal (or earth) is removed when the lid switch operates as I don’t know which way it is and the circuit doesn’t show.

The voltage on pin 5 comes from fuse F36. I think that the voltage should be 3V but not totally sure about this.

Here’s an image showing the lid switch connection and also the fuse etc. The image on the right is just to show where it gets into the chipset which will be hard to measure but try measuring at D801 (both sides - test the diode as well) if you get any voltage/earth condition changing on pin 6.

(click on image to enlarge)

Note: I don’t know if it is a magnetic switch or a light sensor switch so if you measure between pins 5-6 (6-7?) of the button board connector it should change if you wave a magnet over it or cover it up to stop the light. If it is a sensor than you may have to have power connected for it to work whereas a magnetic switch may be mechanical in operation.

If you get no power on pin 5 check the fuse. If you get power on and off (switch operating/releasing - again I don’t know which way but it should change state) check that it gets through the diode.

If you prove that the switch is working OK check and you get power on/off? at pin 4 of U9 when the lid is open and closed perhaps U9 is faulty as it needs to turn on to connect power to the backlights.

Sorry to mislead you before but this one is different to others I’ve worked on it the past.

Also ifixit has an option to post images in your QUESTION, you can’t post them in Comments. Here’s how to do this Adicionar imagens a uma pergunta já existente

@donfurlan

I’ve been fixating on the lid switch and remembered that you said that there was no voltage on pins 21, 22 & 23 on the video cable connector so I thought it may be worth checking back from the video cable connector instead of forward from the lid switch, if you get what I’m saying.

Doing it this way I found that there is a fuse in the backlight power supply (eventually found it). Check if fuse F7 is OK.

If the fuse is faulty, search online for 0438003.WR 3A 32V ceramic fuse to find suppliers that suit you. Here’s an example to give an idea of the cost. Unfortunately with this example the minimum order is 10 pieces but it is hard to just get the one fuse. You may have better luck.

The fuse is an 0603 smd size i.e. 0.06” x 0.03” (metric equivalent is 1.6mm x 0.8mm) but it is always listed in inches by supppliers so you can also search for an 0603 3A 32V ceramic fuse if you can’t find a suitable supplier using the first search method above.

Here’s an image to show where it is located

(click on image to enlarge)

Apologies for not thinking of doing this earlier if it turns out to be the fuse that was the problem

I'm getting too old. ;-(

I wonder if this tool might be good for unsticking without damaging the contacts

https://tinyurl.com/2rbz2k9z

Internet stak

Here’s a general breakdown:

1. Self-Programming (Common on Older Models):
   • You usually enter the vehicle, turn the ignition on/off a specific number of times, press a button on the remote, and wait for confirmation (like door locks cycling).
   • Your owner’s manual or online forums often provide step-by-step instructions.
2. Dealer or Locksmith Programming (Newer Models):
   • Many vehicles 2010 and newer use encrypted systems that require specialized equipment.
   • In this case, a mobile locksmith or dealership is your best option.

At Keyless Entry Remote, we’re happy to help identify the right programming method for your specific vehicle. Just send us your year, make, and model, and we’ll guide you from there!

Programming a key fob depends on the make, model, and year of your vehicle.

Here’s a general breakdown:

1. Self-Programming (Common on Older Models):
   • You usually enter the vehicle, turn the ignition on/off a specific number of times, press a button on the remote, and wait for confirmation (like door locks cycling).
   • Your owner’s manual or online forums often provide step-by-step instructions.
2. Dealer or Locksmith Programming (Newer Models):
   • Many vehicles 2010 and newer use encrypted systems that require specialized equipment.
   • In this case, a mobile locksmith or dealership is your best option.

At Keyless Entry Remote, we’re happy to help identify the right programming method for your specific vehicle.

richard morris check this video and see if it works for your model as well. Or you can try what works for the 2000 CLK . You can reset them with the button that you normally use to adjust your headrest. To reset the rear headrest, which MB calls a roll bar, press the upper half of the button and hold it for 8 seconds until you hear the mechanism engage, then press the lower half of the button to lower the headrests.

Hi Rizal,

The air conditioning works by blowing air through the condensor that's mounted in front of the radiator, which takes away the heat that's being exchanged for cold inside the evaporator. If not enough air is going through the condensor, then it's not going to take away the heat and the car won't blow cold air.

When the car is moving, there's plenty of air going through the radiator, but when it's stopped it depends on the radiator fan to move air through. If that fan has failed you'll get the exact symptoms you're seeing. Open up the hood and verify that the radiator fan is running when the car is stopped and idling with the A/C on. If not, you'll have to try and diagnose whether it's a failed fan motor or a wiring problem, which could include wires, connectors or fuses. Here's what you're looking for.

Great Content. Thanks for sharing.

TYPO3 Agentur