Hi all,
About 2yrs ago, my heater control panel started behaving weird, the lights would flicker on and off and I would hear the sound of the air duct servo flaps moving around, as if someone were continuously changing the direction buttons. Then it actually stopped working altogether, no lights, the only button that works is the fan speed slider and fresh/recirc air button.
Since then I have resoldered every solder joint on the board. I saw it mentioned on a forum. My board had heaps of joints that had cracked, basically every one on the wiring harness connector that is on the smaller board. It fixed some of the problems, but now I have some interesting issues.
The 3 illumination lights work when I turn the headlights on, but only when the key is set to OFF, if it is on ACC or ON the illumination lights turn off. Strange!!??!! Also, the individual button LED's do not light, though I can get them to light if I connect them to a battery.
What works:
-every button
-temp slider
-fan speed slider
what doesn't work:
-illumination
-switch LED's
Now, having traced the lines on the circuit board I noticed that the transistor controls some of the lighting circuits, could it be that this transistor is bad? Is it common for transistors to go bad? Could it have been over powered or something when the solder joints were failing?
I have found out what transistor it is, and a replacement is cheap, but it will take a while to ship here.
Any ideas?
Should I be looking elsewhere?
I have checked every resistor and diode on the boards, they are working to spec.
Also, as you can see in the photos, I have rewired the connection between the boards, it looks messy, but my multi-meter tells me the connection is good. =)
Thanks!
Heres the transistor I speak of.
About 2yrs ago, my heater control panel started behaving weird, the lights would flicker on and off and I would hear the sound of the air duct servo flaps moving around, as if someone were continuously changing the direction buttons. Then it actually stopped working altogether, no lights, the only button that works is the fan speed slider and fresh/recirc air button.
Since then I have resoldered every solder joint on the board. I saw it mentioned on a forum. My board had heaps of joints that had cracked, basically every one on the wiring harness connector that is on the smaller board. It fixed some of the problems, but now I have some interesting issues.
The 3 illumination lights work when I turn the headlights on, but only when the key is set to OFF, if it is on ACC or ON the illumination lights turn off. Strange!!??!! Also, the individual button LED's do not light, though I can get them to light if I connect them to a battery.
What works:
-every button
-temp slider
-fan speed slider
what doesn't work:
-illumination
-switch LED's
Now, having traced the lines on the circuit board I noticed that the transistor controls some of the lighting circuits, could it be that this transistor is bad? Is it common for transistors to go bad? Could it have been over powered or something when the solder joints were failing?
I have found out what transistor it is, and a replacement is cheap, but it will take a while to ship here.
Any ideas?
Should I be looking elsewhere?
I have checked every resistor and diode on the boards, they are working to spec.
Also, as you can see in the photos, I have rewired the connection between the boards, it looks messy, but my multi-meter tells me the connection is good. =)
Thanks!
Heres the transistor I speak of.