COMAND Screen Smoking
08-15-2018, 07:29 PM
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COMAND Screen Smoking
This problem is several years in the making...
TL;DR - My COMAND screen smokes when I plug in the 8 pin power connector.
My wife "hit a bump a few years ago" and then her COMAND Monitor started smoking in the upper left.
It eventually turned off completely, but it is clearly a back-light issue. I can see stuff when I shine a light,
or a sunny day if I look hard enough.
From a cold start, just putting the car into auxiliary mode, the monitor motors function correctly. The screen
comes up, blinks and buzzes briefly once a second for three seconds, then the back-light goes off. The buttons
work, if I am patient enough I can reset the clock when I need to for DST. Just a back-light issue.
I was able to find a "cheap" replacement monitor off eBay for $300 and when I plug it in, it started smoking too!
The issue is with the system the monitor plugs into.
There are two plugs on the rear of the monitor assembly, and LVDS black/silver plug at the top and an 8 PIN
connector at the bottom. The problem is with the 8 PIN connector.
If I could find out what the rear 8 PIN connector connects to, I could check the voltages and make sure there isn't
a short circuit or something. But the wiring behind the dash is a mess.
Does anyone have any resources that might help me? Wiring Diagrams? PIN OUTs?
TL;DR - My COMAND screen smokes when I plug in the 8 pin power connector.
My wife "hit a bump a few years ago" and then her COMAND Monitor started smoking in the upper left.
It eventually turned off completely, but it is clearly a back-light issue. I can see stuff when I shine a light,
or a sunny day if I look hard enough.
From a cold start, just putting the car into auxiliary mode, the monitor motors function correctly. The screen
comes up, blinks and buzzes briefly once a second for three seconds, then the back-light goes off. The buttons
work, if I am patient enough I can reset the clock when I need to for DST. Just a back-light issue.
I was able to find a "cheap" replacement monitor off eBay for $300 and when I plug it in, it started smoking too!
The issue is with the system the monitor plugs into.
There are two plugs on the rear of the monitor assembly, and LVDS black/silver plug at the top and an 8 PIN
connector at the bottom. The problem is with the 8 PIN connector.
If I could find out what the rear 8 PIN connector connects to, I could check the voltages and make sure there isn't
a short circuit or something. But the wiring behind the dash is a mess.
Does anyone have any resources that might help me? Wiring Diagrams? PIN OUTs?
08-17-2018, 07:22 AM
#2
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Various Fiat
This problem is several years in the making...
TL;DR - My COMAND screen smokes when I plug in the 8 pin power connector.
My wife "hit a bump a few years ago" and then her COMAND Monitor started smoking in the upper left.
It eventually turned off completely, but it is clearly a back-light issue. I can see stuff when I shine a light,
or a sunny day if I look hard enough.
From a cold start, just putting the car into auxiliary mode, the monitor motors function correctly. The screen
comes up, blinks and buzzes briefly once a second for three seconds, then the back-light goes off. The buttons
work, if I am patient enough I can reset the clock when I need to for DST. Just a back-light issue.
I was able to find a "cheap" replacement monitor off eBay for $300 and when I plug it in, it started smoking too!
The issue is with the system the monitor plugs into.
There are two plugs on the rear of the monitor assembly, and LVDS black/silver plug at the top and an 8 PIN
connector at the bottom. The problem is with the 8 PIN connector.
If I could find out what the rear 8 PIN connector connects to, I could check the voltages and make sure there isn't
a short circuit or something. But the wiring behind the dash is a mess.
Does anyone have any resources that might help me? Wiring Diagrams? PIN OUTs?
TL;DR - My COMAND screen smokes when I plug in the 8 pin power connector.
My wife "hit a bump a few years ago" and then her COMAND Monitor started smoking in the upper left.
It eventually turned off completely, but it is clearly a back-light issue. I can see stuff when I shine a light,
or a sunny day if I look hard enough.
From a cold start, just putting the car into auxiliary mode, the monitor motors function correctly. The screen
comes up, blinks and buzzes briefly once a second for three seconds, then the back-light goes off. The buttons
work, if I am patient enough I can reset the clock when I need to for DST. Just a back-light issue.
I was able to find a "cheap" replacement monitor off eBay for $300 and when I plug it in, it started smoking too!
The issue is with the system the monitor plugs into.
There are two plugs on the rear of the monitor assembly, and LVDS black/silver plug at the top and an 8 PIN
connector at the bottom. The problem is with the 8 PIN connector.
If I could find out what the rear 8 PIN connector connects to, I could check the voltages and make sure there isn't
a short circuit or something. But the wiring behind the dash is a mess.
Does anyone have any resources that might help me? Wiring Diagrams? PIN OUTs?
Take the 8 pin connector out from the housing. The pins are numbered on the 8 pin block. Pins 1,5 and 7 have brown cables, these are connected to ground. Pins 2 and 6 have red/blue cable and are connected to battery +12 volts. Pin 3 with black/white is CAN A High. Pin 4 is a plain black cable, this is CAN A Low.
Your cheap eBay purchase was probably also defective from the start. These monitors all die in the same manner after a while.
08-17-2018, 09:18 AM
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Thanks for the reply!
I was able to Independently verify the 8 pin pinout is correct.
I even was able to measure the current from pins 1 & 2 at 4mA and pins 5 & 6 at 2mA.
In what way do all these screens fail?
Why did you suggest that I remove the pins from the connector housing?
I was able to Independently verify the 8 pin pinout is correct.
I even was able to measure the current from pins 1 & 2 at 4mA and pins 5 & 6 at 2mA.
In what way do all these screens fail?
Why did you suggest that I remove the pins from the connector housing?
08-17-2018, 09:42 AM
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Various Fiat
The removal of the 8 pin connector is merely to identify the pin numbering. The neon back light corners overheat due to ageing and burn out. There is no replacement part for the back lighting so my workshop replaces the whole display which after a few years dies as well. The display is made in Korea by LG/Philips.We do about 8/10 units per month.
08-21-2018, 08:17 PM
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Update: You were right. The second screen I purchased said it was tested, but I opened it up and the first inductor on the white connector (not sure what the name is) on pin 10 has popped off the board somehow (I know I didn't do it.) And the LCD panel failed the same way the previous one did, the corner was burned by faulty wiring, I guess.
But now I have two boards and between them I am sure I can get at least one working.
But now I have two boards and between them I am sure I can get at least one working.
08-21-2018, 08:36 PM
#6
MBWorld Fanatic!
This is what happens when you overclock 
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