rear defroster
 

My 87 420 rear window defroster is not working. Does anyone know if there is a heating element the heats the wires up somewhere on the car that can be replaced? I like all things to work on the car and that is the only thng not working at the present.

Dave,

You've got to start somewhere: check you have 12V at one end of the window element, and a good chassis connection at the other.

If you don't, work logically back from there to the switch, fuse and eventualy the battery.

Somewhere along the journey the 12V will reappear; then you should know where the fault lies.

Also check that the element hasn't gone high-resistance. By my guestimations, the element should measure less than 1 ohm (ie. Not a short circuit, but close).

Even if you have to splash-out on a DVM, it'll still be MUCH cheaper to prod around yourself and employ a bit of thought rather than auto electrician.

Thanks Paul
 

The old "trace it backward plan". Done it many times. Maybe it won't be too hard to find.

Thanks for your reply....I'll let you know what I find FYI.....

Dave