Another Leccy Window Problem - Honda Prelude this time

oops. forgot to add.... it's a '94 model , 2.3i Manual if that makes any difference.

first off: test your window assembly by just running a pair of leads from the battery, connected one way will be up and vice versa. then go back to your switches and establish that they really work, if they do then you have a wiring fault, probably at the bendy bit at the door hinge or at a connector. switches would be first point of call though.

mrcheerful

I take it you have checked the over-ride switch?

no - where's that?

...of course a thought occurs a millisecond after hitting "send"...

do you mean the switch that's used to disable the window switches typically for rear-windows?

If so, I don't think there is one in this case. At least I've never found one in the 8 years I've had it.

The motor & assembly certainly did work when tested in front of my eyes at the breaker's yard. I'm going to try and run it directly from the battery tomorrow, as the window is currently stuck about 1" open (unfortunately a side-effect of testing it - it wasn't returned to the same position!) and that needs to be sorted anyhow. That would at least show that there isn't some mechanism problem that the motor's fighting against.

The potential switch problem I'm not sure about either, but I'll try and test them tomorrow. Reason I suspect it's not the physical switches is that neither the control switch on the driver's door (both passenger & driver windows can be operated from there) nor the one on the passenger door operate. Unless something has fried themboth I think it unlikely that they would simultaneously develop faults, and I can't see them being wired in series.

Passenger door wiring loom I'm doubtful of. I'm getting full battery voltage w.r.t. chassis for both of the wires feeding th motor, depending upon the direction of the switch(es). That means integrety of both feed paths back to the control unit.

So for there to be voltage w.r.t earth but not w.r.t the other wire that must mean that it's the return path that is faulty through the control circuitry somewhere.

Now, looking at the control circuit behind the driver's side door (and I don't actually _know_ that this has anything to do with the passenger side window - it might only be for the one-touch operation of the driver's side window) it seems to me that this is just not beefy enough to handle the current that would be flowing through the window motor circuit.

Which leads me to suspect that there is a relay involved somewhere (in fact, if there are 2 switches there must be some kind of control circuit, otherwise passenger pressing window up at same time as driver pressing window down would result in battery +ve being connected to battery -ve, resulting in complete meltdown of that particular wiring loom....). If this is the case then it seems like the return connection of this relay is shot.

So, I'm going to hunt around and see if I can find such a beastie.

It is not immediately obvious but:

Both switches must be in good condition and plugged in or the window will not move.

I found this out after hours of messing about!

Ordinary electric windows don't have relays in circuit.

Most common problem is switches, particularly in smokers cars as the ash fills them with insulation!

mrcheerful

OK, thanks. .

One thing I don't understand though is how a dual-control window circuit can work with just two switches wired in parallel and no other control circuitry. If the driver attempts to raise the window at the same time as the passenger tries to lower it, won't that cause a short through the wiring loom & hence blow the circuit fuse? I'd have thought that it would be a quite likely situation to occur, so would have been designed out of the system?

Anyway, I could hypothesise all day, but that won't necessarily help me. Some switch testing to do methinks.

That is the thing, the switches are not in parallel, they are special switches in series.

mrcheerful

Thats what I wondered, but just couldn't work out how. Oh well, not important, but flawed thinking probably sent me down the wrong diagnostic path.

With that in mind, it's becoming increasingly likely that 1) it's a switch, or 2) its an earth connection to one of the switches (it's got to be the return path, hasn't it? I'm getting voltage through to each motor wire w.r.t earth, just not across the wires).

ta.

Except for the one-touch-down function of course.

Well, a bit of both really! The circuit will be similar to the 2-way switching in a domestic lighting circuit.

Chris

GOT IT!!!! Fault with the connector behind the driver's side control panel. Fixed.

Many thanks.

Andy, apologies for the last two responses to your post - there is indeed an isolator, and it has been staring me in the face all these years. Actually, come to think of it I do remember it being there, but with being a 2 door car, never had the need to use it.

Fortunately, this didn't prove to be the problem - was in the "On" position anyway, otherwise I'd have been feeling like the biggest bloody idiot ever. Problem tracked down to connector at back of driver's control panel, sorted now.

Thank gawd for that - would have faced an uphill battle selling the car with a non-working passenger window.

thanks to all.

OK, good to hear. You have no idea how many times I've turned on those switches in the last 20 years ;-)