Rear Defroster not working

Hello,

There is a relay that control the rear window defogger or there's an open wire within the grid on the window. Here is the wiring diagrams for the system so you can see how it works and the relay location along with a guide to test the relay to confirm the issue.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit


Check out the diagrams (Below). Please let us know what you find.

Thanks for this post I had a relay not working so I got a new one for $34.00 all fixed! I love this site.

Why doesn't my rear defogger work in my 2002 monte carlo? I already changed the relay but that didn't help.

Did you check the fuse?
Did you check for power back to the defogger?

[quote:f77239de82="Service Writer"]Did you check the fuse?
Did you check for power back to the defogger?[/quote:f77239de82] I didn't find a fuse for it just the relay and breaker. There is no power to the rear defogger. I tested it with a test light.

Check this 60 Amp fuse:

the rear defroster stoped working. I have power coming out of the circuit when i push the defrost button. The window grid ohm's out ok. I have power on feed wire to the grid when it is unhooked from the window, but when i hook it up the power goes to 0 volts. not sure what to check next.

Chances are the switch is bad and can no longer handle the load from the grid. Check output power at the switch to see if it drops when you turn it on with the grid is plugged in. If it does, replace the switch.

Let me know what you find.

Joe

the switch lookes fine. I have 14 volts coming out of the circuir breaker, but at the grid 11.5 volts. also when i plug into the gird and loose power i noticed when i unplug it the voltage goes from 1 volt and slowley climbes back up to 11.5, is there anything between the circuit breaker and the grid? seemes like there may be a broken wire only maybe a coupple of strands holding on. don

THere isn't anything between the two. It does sound like a broken wire, but the voltage wouldn't rebuild. How did you check the switch? I went through a similar problem on a dodge that ended up being the switch. It showed normal voltage until a load was on it. At that point, it couldn't handle the draw and output voltage would drop.

the power does not go through the switch. it is only control power to work the relay. I think the wire from the circuit breaker is bad some where. going to ohm the wire from the breaker to the window connector to day. this should tell me if the wire is any good.

Was wondering on why my rear window defrost all of a sudden, just stopped working. The light comes on that is on the dash, but the rear window never clears up. Is it possibly a fuse or the strips on the window?

If none of the grids work, check fuse first, then relay (should hear it clicking when you push on the button), then check each tab on the two vertical bars (one on each side of your rear window).
Good luck

That is a good idea. There could be a break in the wire.

As far as the relay / switch, I understand what you are saying, but power still goes through the switch. It's just a thought.

I am having the same problem with a 03 Monte. I haven't pulled the switch out to check it yet, but when I do it seems like a simple jumper wire will tell if it's the switch that is the culprit. I will keep you posted.

I have always thought that the purpose of the switch was to provide a small load to the relay, so the relay was handling the bulk of the load.

I took the rear defog relay module out of fuse box on passenger side dash. I would like to know if there is a specific way it plugs back in. It COULD go in two different ways. There is a "corner cut off" on the module, should that be on the top left or bottom right when plugging back in? Ididn't want to plug it in and maybe screw EVERYTHING up Thanx--Jim

Welcome to the site. Use a testlite on relay socket, how many hot terminals, everything turned off. If only one is hot, that should be L3. There may be a wiring diagram on top of relay, look for the prong that matches up with L3.

no rear window defrosters


currnetly my rear window defrosters are not working. I checked and all my fuses are good and I have a position terminal connection at my rear window defrosters. Is this an internal problem inside my cllimate control center or is there something that I've missed.

If my climate control center went bad. Can I replace my analoge display with a digital display.

do you have voltage at the terminal at the rear window

This is the problem!!
Burnt connection inside passenger side fuse box connector
Easiest repair, is to solder in a new wire from harness on backside of fuse box
Generally referred to as an “overlay “

Excellent addition to this thread! Please feel free to help out whenever you are on the site :)