Rear Window Defroster Testing

by Karl "Aufever"

I have checked continuity & I actually have it across all the wires going across the window. Is that a miracle or what? I was changing the window seal out this last weekend & decided to check it out & was amazed.

I have never found testing each line going across to be accurate with an ohmmeter. You have a positive common connection on one end of the glass and a negative common connection on the other end. Let's say you have 10 lines. Let's say only one is making a complete circuit across. ANY other line you check with the ohmmeter will show a circuit, zero resistance, because you are reading the one good line. Now if you cut that good line, then you could check each other one....providing you didn't have one more good line..... The only true test I've found is to get the window frosty and apply voltage, then see which line isn't clearing the frost.

[Broken lines can be repaired with special brush-on metallic paints made for this purpose found in auto parts stores.]

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