Rear Defrost Not Working

[90civicrider]

it's getting cold and my widows fog up really bad.
but my rear defrost doesnt work.

When i push the switch the light on the switch turns on.
the longest i've had it running is 1 hour and it was still not defrosting.

I took out the swith and made sure the connections were right.
then i checked the rear connections attaching to the window, and that looked fine also.

anyone know what else could be wrong?

[SkyNex721]

Yeah mine works but only 4 lines actually heat up. whats up with that?

[91b16sedan]

Repalce the rear defrost fuse in the fuse box in the engine bay. That is why my rear defrost did not work and now it works like a champ

[enginerd]

If you have a hatchback, look in the window for a unit that hooks up to a female connector. One of my old cars had a rear defrost that quit working and the connector was just loose.

[Killa_CRX]

Check every one of the defrosting wires that goes across the back window from the inside.... if you can see the copper wiring instead of the blackish insulation then that particular line is no longer functional.... if you're wondering "What blackend insulation?" you're probably screwed as far as getting it to work ever again is concerned

[90civicrider]

I checked all the defrosting wires and they all seem to be in good condition. As for the connectors i pushed them in nice and snug and still nothing.

Originally posted by 91b16sedan
Repalce the rear defrost fuse in the fuse box in the engine bay. That is why my rear defrost did not work and now it works like a champ

Which fuse is it?
it's in the little box thing on the passenger side right?
i dont really wanna pull all the fuses to check them,
I'm scared i will reset somthing or screw somthing up :eshooter:

[spy54]

when you pop the panel hiding your fuse box it should have like a chart of which one it is

[kris]

Also, rather then have your vent settings set on recirculate. Set it to fresh air. That will help prevent fog buld up. You can also kick the AC on, with the heat set, and that will help de-humidify the air.

[91b16sedan]

It is a 20 amp fuse. If you are standing on the passenger side looking acroos the engine it is the third one on the left side of the fuses. I took some pics of the top of the fuse box and then the inside to show you just in case.

This is the photo of the diagram on the outside of the fuse box that shows you where the fuse is.



This is a photo of inside the fuse box that shows which fuse is the rear defrost fuse

[sastanley]

You know what? That shit ^^^^^^^^ rocks...I am glad some peeps utilize their digicams to help out us peeps...

I once had a '78 Civic that had only like 3 or 4 defrost lines on it that worked. They do sell aftermarket defrosters..

I'll whip out my volt meter and try to figure out how to test the connectors at the back window and see how much voltage you should be seeing back there. But, as noted, if the defroster elements are damaged, you won't get much out of them. Window tint can often have adverse effects on defrosters too..

How's that b16 comin' b16sedan?

[90civicrider]

Thanks alot for the pics!!
i check it all out and the fuse is in perfect shape.
I do have my windows tinted with Limo tint.

when the defroster is on NOTHING i mean nothing happens.
not a even a little drop of water being melted.

[91b16sedan]

90civicrider
Did you just look at the fuse or did you test it with a test light. Some times there might be corrosion between the male and the female connections in the fuse box. When a fuse is busted the little metal piece inside is broken and not touching.

Shawn
the swap is coming along well. I am currently pulling the zc and I recieved the b16 today. I hope to have everything done and up and running by the following weekend.

[sastanley]

91b16sedan - Good to hear on the swap!! Keep at it and keep us up to date!
Jeff - Sorry I was a big slacker and I forgot to check with my meter. I have a Q for you....have you had any other problems with electrical stuff in the back of your vehicle? My '85 Civic once had ALL the taillights & brakelights stop working. When they put the car together there is a big-ass connector (on my '85 it was between the front and back door under the carpet/door trim, right at about the B pillar) This connector connects the back half of the car's electrical system with the front half...Mine was not making a good connection. I took it apart and sprayed contact cleaner and it helped a lot. I occasionally have my 3rd brake light in my '91 not work and I suspect the same problem..so far opening and slamming the door while my foot is on the brake fixes that!! - lol - also...your switch could still not be getting current to your defroster, even if the light is lighting up. I am sure there is a relay somewhere in the car for the defroster and it could be bad or have a loose wire..etc.etc.. The first test for you is if you have voltage at the defroster itself. Sorry I forgot to check, I'll try to remember tonight.
Later!