Beiträge von Alex.L

Zitat von Go4IT

The TP you highlighted is "JTAG GND". One of many possible GND positions on the board (they are mostly all connected to the same earth, just measure with your DMM). The chassis case may be decoupled from GND by some ohms, so this might distort the readings.

Ok, now that you know you have to deal with the old graphicsboard, let's see. One idea again is to power the unit up on the bench without the maybe faulty keyboard pcb.

I tried it yesterday when I tried with the new card. But I tried again just now just to be sure. I'm getting a white screen with some blueish vertical lines (very dim).

I'm not getting any connection between the ground point and chassi or JTAG ground. No numbers or indication of bad connection even.

Zitat von Go4IT

Just that it's been said: If you want i can also help you with repair/sparepart. Even if transportation charges are high, it may be cheaper than "lessons learned charges" So before you buy something from a stranger, don't hesitate to ask me first.

That's a really good idea mate!

Is there anything else I can try by myself before "giving up" and sending it to you?

Thanks again for taking your time, I know you must get a lot of questions from a lot of people!

Zitat von Go4IT

First of all, this will be a journey, not a quick trip, so prepare to spend a lot of time for this to fix. It's perfect to have an alternative meanwhile, as you will by adding a separate climate control unit. Hope you electronic skills are high and also your equipment. You should be familiar with SMD soldering/desoldering and should have a digital oscilloscope, measurement equipment and an adjustable power source.

To power the unit you just need to apply 12V (~1.8 - 2.0A) to the pins 12 (GND) and 15 (+) of the Quadlock, that's enough: https://mk4-wiki.denkdose.de/artikel/ audio_navigation/quadlock#supply

The "white" you see is due to the background illumination of the display. Normally the crystals inside the LCD screen are aligned to shade the light from it and/or form color filters to only pass color components of a specific amount. This way the pixels turns black/white or any color between. Such LCDs needs a lot of different voltage to work. They are derived from this converter.

You should always measure to GND:

The 5V you measure is the input power of the boost converter MC34063 (the chip in the middle of the red circle). It shows that the converter is getting the needed input power to work, good!

The "LCD+" should be the output voltage the converter produces. In my writings it was about +12V (which fits your measuring). The "LCD-" should produce negative voltage, -8.3V.

Check the rectifier diodes (BAV99, SOT-23 case) as they might reported (use a simple DMM for it):

Also check the caps at least measure resistance if not capacity. The should not have a resistance, if they have, they are melted.

Alles anzeigen

Ok, so I went back and checked this again.

LCD+ is 12V

LCD is -9V
5V is correct.

The rectifier diodes are alright and capacitors don't have any resistance.
In other words, I can't find any issues with anything from this post.

Would really appreciate any other suggestions on how to proceed

Edit: But, the earth point isn't earth on mine. I need to measure against the metal cage to get voltage readings.

Edit 2:
This is ground though.

Zitat von Go4IT

You bought the wrong board.

The left one is from your MCA-Plus, the right one (new one) is a non-rvc board of an NX. This can't work.

Remember as i mentioned that an spar MCA-Plus graphicsboard is nearly not available on the market? If somebody sold it as a MCA board, he cheated you...

Yeah, so I noticed. I'm not sure it was intentional though, since people are having a hard time seeing the difference between the different kinds.
Everything is marked MCA and NX and so on.
Expensive lesson though.

Got a contact on Talkford with an MCA, but no video for the reversing camera. Around €380 though since it's from the UK...It's almost as much in customs and tax as he wants for the unit, stupid Brexit.

I'll see if I can try that tomorrow.

But I just realized something and I don't really know how I missed this....

New card on the right.

Zitat von Go4IT

Try to run the unit by only attaching the graphics board to the main board, with LCD connected. A bit fiddly but doable.

Tried it now. The 2015 update CD is still in it now, because it doesn't want to come out anymore...
The CD spins up, after a few seconds the screen comes on (blank), then the CD stop and the screen turns off. With no power button I can't see if it want to come on again.
Thanks!

Zitat von Go4IT

You can connect any 12V DC source (up to 15V) which I able to provide 1.5 A to drive the unit on the bench. See Wiki (Quadlock) for +12V and GND. You can then fully operate the unit. I would suggest this to ensure nothing else is causing the issue.

The climate controller is completely independent from the satnav, it is just physically mounted under the satnav case. It receives control commands throught the MS-CAN bus. I don't see any correlation here.

What i had expected is that you have a fully working screen after replacing the graphicsboard, only encountering strange texts as the firmware on the board does necessarily match the one on the mainboard. But this is a minor issue which can be solved by running the update.

Thanks again!
Ok, that's very good to know. I have already run it a couple of times on "the bench" with the same results as in the car unfortunately.
Have you any idea if the issue right now could be because of a broken firmware?
I'll try some more, and double check connections everywhere.

Edit:
It's obviously been a moisture issue at some point.

Edit2:
Regarding the graphics card, no it was probably unnecessary but it was a logical first step. Not much to do about that now.
Now I'm wondering if I should buy another used MCA unit or go with an after market solution. The problem is getting everthing to work that I want to keep on the car (in that case). The reversing sensors and I would like to keep the spare wheel subwoofer. Convers+ I don't really use anyway so I can live without that. Many after market units have a reverse camera option so that shouldn't be an issue.

I've cleaned the PCB, but still not working.

Hadn't removed the PCB for the LCD and button lights.
I'm thinking that this is quite likely moisture ingress unfortunately.
I'm sorry about the picture quality.

And now I get this. It doesn't show up at first when plugging it in and I haven't been able to figure out what makes it show these lines, but I don't think they show up unless I plug in the AC connectors in the black box controller.
This is driving me a bit crazy now. And I can't shake the feeling that maybe something else is wrong.

Zitat von Go4IT

Well, this is unexpected... I would suggest to inspect the keyboard PCB for fluid/corrosion

Yes it was.

I've already gone over every millimeter of all the PCBs, so it's probably not that (unless it's impossible to see with the naked eye).

When powered on separate from the car, should any text be visible on the display?

Edit: I did try to run the 2015 MCA upgrade, that's how I got Convers+ back (even though its still greyed out). Might it have to do with that?

Edit 2: No difference today unfortunately.

Small update again .

Got the graphics card today, installed it, reprogrammed the BCM back to support the AC controller and display.

Now I have the correct backlight but the screen is still not showing any information...

But, the AC controller is responding and I can turn the screen on and off. There are no lights on the controller buttons though. Now I've disconnected the battery again over night and I'll resume tomorrow.

Still open to suggestions.

Thanks!

Just a quick update.

I found a guy in Poland selling parts from his MCA head unit, so I bought the graphics card from him. I'm hoping this will solve my issue.

I will try and repair my broken one in any case, but I won't be in the same rush/panic ?

Thanks so much yet again for your time and effort!

Oscilloscope is something I don't own unfortunately, will have to look into borrowing one maybe.
I have done SMD soldering on one or two occasions before, but not extensively.

With Christmas tomorrow this will take a while, I'll report back when I've checked of your list here.

LCD+ is 12V

LCD is 2.4V

5V is 5V

Not sure if/what you wanted me to measure between LCD+ and -?

Thanks again!

Edit:
So I put the head unit back together again and plugged it in to the car. Same thing, white blank screen.
Then I put in my CD with the 2015 MCA update in and after a while the Convers+ menu came back, still greyed out though since I cannot input the radio code.
The screen started to respond to button pushes (the ones around the screen) by trying to change to the relevant screen I suppose.
I really wish there was a way to input the code without the touchscreen...

Zitat von Go4IT

Around these chips is the boost converter for the base LCD voltages:

Measure these voltages:

Thanks so much again Go4IT!

I'm guessing it's possible to power the MCA outside the car? By applying voltage to the relevant pins on the quadlock connector.

Edit: at the same time, the LCD seems to get power since it lights up, but maybe that is separate from actually showing stuff on the screen.

Is there some website where you can search for used car parts in Germany, except Ebay?
Here in Sweden we have Bildelsbasen.se, I'm wondering if you guys have something similar.

Zitat von Go4IT

I fear there is no short answer to this. I ran into the same trouble a while ago and it looks as if there are several possible faults which may cause this kind of issue.

What i can tell is, that it is completely untelated to the mainboard (and also the mainboard RAMs) and only located on the graphicsboard.

I have two such defect units at hand, one from an McA and one from an NX. I spend many many hours of searching, measuring and component swapping, mostly without luck. On the MCA it looks like it was just a defect capacitor, shorting the converter of the LCD voltage boost regulator output. But this is just a hunch.

Unfortunately there are no spare boards available on the market, especially not for the MCA+ with video input.

Thank you so much for taking the time to answer me!
Then I'll probably not spend any more time on it, too bad
Considering the prices for a used replacement unit, I will probably go with a separate AC controller and then add another stereo. Don't know if it's better to look for a third party unit or go with the cheaper stereos from another Mondeo though. If anyone has any thoughts on this, please feel free to let me know
Would be nice to keep the reverse camera though as it really helps when caravanning.

Edit: Do you know which capacitor on the MCA? Might give it a go replacing that in that case, before giving up.

Edit2: I've also lost Convers+ but I'm guessing that has to do with the head unit not working.

Thanks for answering Endurance.

I'm starting to think maybe it's the LCD that has failed, since everything still worked until I removed the battery. If the RAM was bad, then I'm thinking that the radio and AC wouldn't have worked.

Zitat von Ossi

Er hat die Antwort https://mk4-forum.denkdose.de/user/6347-go4it/

Vielen dank!

Hello,

I apologize for posting in English on a German forum, but my German is really, really bad(from Sweden).

I'm usually active on talkford, but I haven't found anyone with enough expertise to help me with this problem.

I've had issues with the MCA display flickering and showing artifacts before, but since about a week I get no image at all anymore. Sure it might be broken and needs replacing but I really want to look at every possible solution before buying something else (or a replacement).

I have removed the battery twice to see if something needed resetting. Before the reset, everything worked but no image on display (even though it lights up). After reset, nothing works, maybe because I cannot enter the radio PIN on the display. The heating seems to be stuck at like 28-30C and the buttons and wheels for controlling the temperature doesn't do anything anymore (they worked before, but you had to guess the temp since you couldn't read it of the display). The radio worked as well.

I took the entire unit out and put it inside to heat up and dry up (if there was any condensation) but it hasn't helped. I've opened it up and I can't see any issues at least. No loose connections or traces of moisture on the chips.

I read the DTC's with ForScan today, but I'm unsure if the adapter I have is good enough to get everything. I've attached the saved information to the post.

Any suggestions or tips would be so very much appreciated, because I'm so stuck right now and a replacement unit is very expensive (if I can even find one).
And we really need the car at Christmas...

If I have missed any information please let me know and I'll append it asap.

The most important thing right now is to get the AC-controller working. The display/radio/navigation is seconday.