Thread: Rear defroster
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9FF 9FF is online now
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Join Date: Sep 2011
Location: Florida
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Ok think logically. When you operate the switch and get 12v on the left (supply) side, then your fuse, switch, relay and supply side wiring are all good. If you also get 12v on the right (ground) side then your defrost element is also good. The reason it’s no heating up is bacause you are missing a ground on the right side, without a ground the circuit is incomplete and the 12v will simply hang around on the right side strut.

Look at where the defrost element exits the glass and enters the right strut, it then runs down the right strut to a ground point on the chassis. It is that ground point where your problem likely lies, it’s not grounded for some reason and you need to inspect why.
Mike A
1986 944 (Street); 1986 944 (Track); 1986 951; 1989 951 (3.0L 8V); 2000 996 Cab.
Old 02-11-2019, 07:57 AM
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