Defroster Voltage

cherrington17 · 05-16-2011, 05:46 PM

Can someone run out and turn on their rear defroster, then give me a voltage reading off the two wires that connect to the window?

Mine seems to jump from 200mv-400-600-1.2V then back down to 200.

Is it suppose to do that, or is there something wrong with my defroster module??

Ttop191 · 05-16-2011, 11:45 PM

Im pretty sure it's supposed to read 12v out of the module...then of course decrease as it crosses the glass...but if you are reading mV its definitely bad

cherrington17 · 05-17-2011, 08:03 AM

checked on my dad's Escape... 10.57V constant

dammit.

So I need a new module... and the wires that connect to the window. argh.

cherrington17 · 05-17-2011, 10:13 AM

Addendum : I need an alero tested now.

What is the top left contact in the rear window? (Facing the window from the inside)

That one has the jumpy voltage. The two defrost contacts (one on each side) read as 10.7V. So the defroster is fine... but that top one...I have no idea what that even does???

dmcb2120 · 05-17-2011, 10:54 AM

Radio antenna ??

cherrington17 · 05-17-2011, 01:27 PM

why would the voltage bounce around like crazy on the antenna?

(i assume thats the top of the "lines" across the back of the window)

widbyj · 05-17-2011, 05:41 PM

Cause radio is AC...

cherrington17 · 05-17-2011, 05:46 PM

well... then I guess thats normal then.

alright, thanks guys. No other problems to note.