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A Permanent Dim Dash Fix

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A Permanent Dim Dash Fix
by Pat Swayne

If your dash lights are dim, it may be because the dimmer transistor is not making good contact in it's socket. If so, here's a permanent fix for the problem. (The dimmer transistor is what the dimmer control on your dash is connected to.) You need to be good at soldering to do this. If not, get someone who is to do it for you. You'll need a good soldering iron with a fine tip like this:
Soldering Iron
The soldering iron should be about 40 watts, or better yet, a temperature controlled one set to about 650-700 degrees F.

First, remove the dash light transistor assembly. If you lay on the floor of your car with your head near the gas peddle, and look up, you'll see it under the dash. When you've removed it, place it on a table oriented like this:
Dimmer Transistor Assembly
Here you can see the transistor pins coming through holes in the contact blades. The amazing thing is that it works at all this way -- the contact surface between the transistor pins and the contact blades is so small! Do not disassemble the unit (unless, of course, you followed some bad advice before and removed the white heat sink compound and need to replace it.)

Take a small knife and scrape the contact blades near where the transistor pins come through -- just enough to roughen them up a bit. Now apply solder to the blades and pins so that it flows onto both. This is where soldering experience is needed. The blades will act as heat sinks and suck the heat out of the soldering iron too fast if you are not careful. Don't worry about the transistor -- it will not be harmed by the soldering. When you are done, it should look like this:
Soldered Dimmer Transistor
Notice how the solder flows smoothly from the blades to the pins. If it doesn't look like this, it may not be making contact, and will do no good. Now replace the unit and try out your dash lights. They should be brighter now.

If they are still not bright enough, you may want to try brighter bulbs. They will NOT harm the transistor (as others have said they might), but the extra heat of them might melt some plastic.

The reason why brighter bulbs will not harm the transistor is that the only time the transistor dissipates any appreciable energy is when the dimmer is turned down. Chances are, you're not going to turn the dimmer down if the problem was a dim dash in the first place. And in any case, the transistor is designed to handle more current than the protecting fuse, so as long as that doesn't blow, you're fine.

If you should ever have to change the transistor, use a "solder sucker" (available at Radio Shack or Fryes) to remove the solder.