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Discussion Starter · #1 ·
I have 12 bolts in the driver side wire and 0 on the passenger. The fuse and relay are fine.

I do not see any broken wires on the glass itself. Where do I go next to figure this out? Thanks
 

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Hey Dark,
When you say you have 12 Volts or 12 Bolts on the drivers side…..is that 12V to chassis ground?
On the other side. Is your measurement across the the rear backlight of from the terminal to chassis ground?
with the car off, what is the resistance across the backlight’s terminals with one terminal disconnected from the car?
BTW a small crack in the conductive trace can be very easy to miss.
 

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Discussion Starter · #3 ·
Hey Dark,
When you say you have 12 Volts or 12 Bolts on the drivers side…..is that 12V to chassis ground?
On the other side. Is your measurement across the the rear backlight of from the terminal to chassis ground?
with the car off, what is the resistance across the backlight’s terminals with one terminal disconnected from the car?
BTW a small crack in the conductive trace can be very easy to miss.
That is 12 volts from the chassis ground.
I will check resistance later today. Thank you
 

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Now you said you had Zero volts to ground on one side. Did you measure the resistance to ground….on that terminal? Was that side even connected to ground?
If it was not connected to ground and you have a brake in the defroster traces, you could measure zero Volts. But it would be very low resistance to ground if it is connected to ground….not an open circuit.

I suggest you get yourself a bottle of rear defroster conductive paint. With that in hand, you can measure the total resistance from input to output on your rear glass.
if it’s an open circuit, it’s time to find the brake in the conductive traces.
You can do it via resistance or voltage…if you know what your doing…YMMV….
Once you find the brake, a little bit of the conductive paint…like a pin head of paint, will bridge the brake in the conductive trace…follow the directions on the paint and make certain you follow the cleaning requirements.
 

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Is the tint covering the grid? Do you have a 12 volt test light with a needle sharp point? You can test by puncturing the tint. The FSM says to test along each grid strip. There should be bright light at the power end, dim in the middle, and nothing at the ground. Each strip gets tested. If bright light along the strip then a bad ground connection/ break on that strip. Unlikely all strips would be broken at the same time but you never know. More likely a bad ground at the end.
 
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