Troubleshooting question on the rear defogger grid

[craigh]

My rear defogger has segments that to not heat and subsequently do no defrost/defog the rear window. I decided to tackle this today A visual inspection showed no breaks in the grid lines. I ran a multi meter from the drivers side power tab and checked continuity across the grid to find breaks. There were no breaks found. Zero ohms across the entire grid. I am not seeing where the issue may be. I do have the grid repair kit with the the small bottle of conductive paint if I can find the breaks. Does anyone have any thoughts as to troubleshooting this or what I am up against here?

 

[JustALs]

not sure but I would get a magnifying glass and put on the rear defrost when its iced up, and inspect each start and end of non working lines, is there 12v at the connector?

 

[craigh]

not sure but I would get a magnifying glass and put on the rear defrost when its iced up, and inspect each start and end of non working lines, is there 12v at the connector?

Power is there and is not the issue. The various segments are not working. I think I need to try checking continuity on the individual segments. I am trying to get this fixed before I get the windows tinted. 90 degree weather right now so not really frosting up, even here in Minnesota.

 

[JustALs]

@craigh Just get a 5% tint and forget about the issue :') jokes..

I hope you find the problem tho,
an old friend I knew had the same issue and he couldn't find the problem so he just got another window at the salvageyard for cheap

 

[craigh]

@craigh Just get a 5% tint and forget about the issue :') jokes..

I hope you find the problem tho,
an old friend I knew had the same issue and he couldn't find the problem so he just got another window at the salvageyard for cheap

MN limits tint to 50%! Unless you have a doctors prescription. I stopped at the tint shop the other day and they said it was pretty easy to get a doctors prescription so I am going to try that route.

I also found out how to find the breaks. I was using an ohm meter and the resistance was zero all around so I could not find breaks. But to find the breaks I needed to start the car, run the defogger and measure the voltage on the grid. It drops from 12 volts on the passenger side to about .6 volts on the drivers side. So I found six breaks in the grid. Used masking tape so I could get a fine line stencil on the grid and so far I have confirmed I have fixed four of them. This is going to work!

 

[clubairth]

Good repair job!
Just 2 more to fix.
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