The new SR5 cluster I bought seems to have some black crap on the copper connecting points for the plug in harnesses, this is on the flismy plastic printed circuits on the back of the cluster. Can I use rubbing alcohol or is there something better to ensure proper contacts?

 

Contact cleaner is the preferred substance, but here's a tip - use a pencil erasor.

 

An eraser will work, just don't use it too hard and use a standard pencil eraser, not one for ink.

 

but WHATEVER you do, Do Not use carb cleaner.... :pat:

I found out what the dealer charges for a 4Runner rear window switch after using carb cleaner to flush coffee out of it. Even the body of the switch melted in my hands...