Hard top defroster....help?

[pwrslider]

I just picked up a hard top for my 72 350SL.....it has the cable plug that fits into the side plug.....but the rear window doesn't have those tell-tale wires in the glass that a normal defroster has..... When I hit the defrost button on the dash...nothing really happens.

1. Do I actually have a defroster....with no wires in the glass?

2. How come it don't work?

3. Should I just continue to use my manual defroster....(hand and a rag??)_

any help would be great.
thanks

[Philoprof]

Originally Posted by pwrslider

I just picked up a hard top for my 72 350SL.....it has the cable plug that fits into the side plug.....but the rear window doesn't have those tell-tale wires in the glass that a normal defroster has..... When I hit the defrost button on the dash...nothing really happens.

1. Do I actually have a defroster....with no wires in the glass?

2. How come it don't work?

3. Should I just continue to use my manual defroster....(hand and a rag??)_

any help would be great.
thanks

The hard top of my 380sl doesn't have any visible wires in it either, and it always worked fine. When I put it on last winter, however, it wasn't working, even though there was power to it. (You can use a multi-tester to see if your plug is energized.)

The only alternative, I guess, is to get one of the universal grids that JC Whitney sells, though it won't be as transparent as the original.

Please let me know if you find out what the problem is.

Good luck,

Bill

[dpetryk]

Look really close at the glass. There are small wires embedded inside the glass not on the surface like most. Hard to see. It "dont work" because it is not getting electricity. It could be a number of things like fuses, wires, relays, connectors and everything in between.

[Philoprof]

It's easy to check: turn it on and put the leads of a multi-tester into the defroster plug socket. If you've got juice, there's a short in the grid. You can then test the grid's continuity by putting one multi-tester lead on each of the plug's prongs and passing current through it. No current, no continuity.

Bill

[pwrslider]

Thanks!!

It looks like I got juice.....It just takes the grids 15-20 minutes to warm up the glass....

is this normal for the year....1972?

[dpetryk]

How cold is it? The colder it is the longer it will take to melt the frost.

[pwrslider]

not that cold....I'm in Ca. so we dont really even get frost...just heavy fog...... it's more of a condensation problem....

[ScottinSoCal]

Originally Posted by pwrslider

not that cold....I'm in Ca. so we dont really even get frost...just heavy fog...... it's more of a condensation problem....

Water condensation is going to take longer than ice. I'd say that's normal. I'm right on the coast and all my newer cars take that long to evaporate the fog off the windows in the morning. I was in New York state before Christmas and melting the ice off took less than 5 minutes.

I never have the hard top on my SL, so I don't know how long that one takes.