Hello, I just stumbled across this forum and need help with a problem I am having.
I am a computer and laptop repair tech and do the odd bit of soldering for dc jacks, caps etc but thats about the extent of my electronic knowledge.
The problem is with a cars instrument cluster which I am trying to repair for my Dad. the backlight has gone and needles have stopped working. Now it is a common thing with this particular car (merc s class) and there is qite a bit of info on what parts to change. Apparently these are the parts that fail on the pcb; 1 Transformer and 3 mosfet transistors, which I have de soldered and soldered on new replacements. Now the instrument cluster does work but all 3 of the transistors get hot, and 1 of them gets really hot and starts to smoke after 30 seconds of having the igntition on and the instrument cluster lights then start to flicker on and off. If I unplug and let it cool down then it goes through the same cycle. I have asked about this somewere else and somebody suggested replacing the 330 coil(which looks like a small capacitor next to the 3 transistors but I did test it and the resistance seems normal. I will show pictures below of the parts on the pcb.
I would really appreciate any advice. Thankyou.
Luke.
Pic of Transistors.
Pic of red Transformer on seperate pcb.
**broken link removed**
I am a computer and laptop repair tech and do the odd bit of soldering for dc jacks, caps etc but thats about the extent of my electronic knowledge.
The problem is with a cars instrument cluster which I am trying to repair for my Dad. the backlight has gone and needles have stopped working. Now it is a common thing with this particular car (merc s class) and there is qite a bit of info on what parts to change. Apparently these are the parts that fail on the pcb; 1 Transformer and 3 mosfet transistors, which I have de soldered and soldered on new replacements. Now the instrument cluster does work but all 3 of the transistors get hot, and 1 of them gets really hot and starts to smoke after 30 seconds of having the igntition on and the instrument cluster lights then start to flicker on and off. If I unplug and let it cool down then it goes through the same cycle. I have asked about this somewere else and somebody suggested replacing the 330 coil(which looks like a small capacitor next to the 3 transistors but I did test it and the resistance seems normal. I will show pictures below of the parts on the pcb.
I would really appreciate any advice. Thankyou.
Luke.
Pic of Transistors.
![10410-buz102s in dash.jpg](https://static.electro-tech-online.com/imgcache/10410-buz102s in dash.jpg)
Pic of red Transformer on seperate pcb.
**broken link removed**