Bass

Hey Guys

04 with a hardtop set-up (not on now) - and just using the soft-top

seems when i press the rear window defrost switch the light lights up but the window does not defrost - futhermore the light on the switch will stay on indefantly (i though these things shut off after a certain amount of time)

I can certianly remove the hardtop harness to see if that's what the problem is but before I do is there an easy way to check the voltage

Thanks
Steve

fmah

I am assuming that the '04 has the same circuitry as the '02. If that is true, (most likely) there is a switch in the left side of the mount for the hardtop that switches a relay between the two possible defrost circuits (the one on the hardtop and the one on the softtop). I would make the diagnosis in the following fashion:

1. Verify that a voltage is/isn't going to the softtop defroster grid. You need to attach a voltmeter to the two wires going to the softtop and check for 12 volts when the defroster switch is "on". If there is a voltage, then the grid may be open. Honda has some conductive paint that can be used to bridge any breaks I think.

2. If there is no voltage, but the hardtop is off, this would mean that the switch in the mount is bad or stuck, or the relay is defective. I've never seen the switch, since I don't have a hardtop, but it should be visible when you look down on where the hardtop fits into the mount. See if the switch is stuck in the down posiition. This would make the vehicle electronics think that the hardtop is installed and turn off the softtop circuit. To actually verify that the switch is working if you can't get it to work by poking at it, you would need to remove some of the finish panels and check the wires. I think it's a green wire to that switch that gets grounded. Also, if that switch is working, you should hear a relay latching when the switch is pushed. I don't recall the location of the relay, but the car's pretty small, so you couldn't miss it. That's different from the relay near the fuses at your left knee which switches the power to the defroster circuit. Anyway, that hardtop switch does definitely activate a relay directly.

3. The operation of the defroster, except the hardtop switch, is controlled by the onboard computer. In other words, the fact that the light remains on is because the computer is keeping the circuit on. I bought this switch orginally to use in my '01 when I had the glass window '02 softtop installed. I was disappointed to discover that it was only a momentary switch, i.e., it signalled to the car computer that you wanted a defrost, but didn't stay closed after you pressed it. I had to change it internally to turn it into a DPDT switch. The computer turns off the defroster when it wants to, after a predetermined delay. Does it turn off after a while, or does it stay on forever?

If I had to guess, I would guess that the hardtop switch is stuck. My second guess would be that the defroster grid is open on your softtop.

Hope this helps. Check the Helms manual for a circuit diagram.

koala

haha. When I had my hardtop installed on my '04, my defrost never worked either. I removed the interior panelling behind the driver seat, and found one of the clips was not clipped securely.

This was of course after trying numerous other things (including taking some of the plastic off the hardtop to look at all of the wiring hidden inside of it).

Good luck!

Bass

Thanks guys i'll check the connections with a meter today

IU did check the wiring and all plugs were connected