• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Power window auto-down mod

aj164

Member
Joined
Jun 5, 2003
Location
C.S., TX
I did a search and didn't find this mentioned, so here it is:

If you want automatic power windows (auto-down, express down, whatever), here is what you need to do:

Obtain :badboy: the auto-down relay from a Volvo 850. (located in the center console on the wiring that comes from the window switch cluster)

Cut this relay from the wiring harness. There are four wires:

+ power (blue)
- ground (black)
control in (yellow)
control out (green)

For auto-down, splice it into the wiring of your window of choice. Looking at the bottom of your window switch, you'll see four contacts:

+ power (yellow-red)
- ground (black)
window motor + (color varies)
window motor - (color varies)

1) Splice the relay power and ground to the window switch power and ground. The relay gets power when the ignition is on, just like the windows.

2) Splice the other two relay wires in series (between) _one_ of the window motor wires. The yellow wire goes to the wire coming out of the switch, and the green wire goes to the wire leading to the window motor. If you grab the wrong wire, you'll have auto-up instead of auto-down.

That's it!

----


-Adam
 
Last edited:
ha, cool. i was jsut thinking about this last week too, I even have the 850 wirign harnress to snag it from, thanks for the tip!
 
Yeah - I edited out the part I wrote about putting the relay upstream from the switches. It was a bad idea. Keep it after the switch on the window of your choice (as described above).


-Adam
 
Sweetness!! Say you want the driver's side auto-down...is it timed so that if you depress the switch quickly it automatically goes down versus holding down the switch if you don't want the auto-down at that time?
 
has anyone tried this for a sunroof? i wonder if its too much load. would be nice for my s70. also autoloc sells a kit for this, i read an install a couple years back in the foca (fiero owners club) magazine. would be nice to do a all switch, like on a4's where you can roll up all w/ the key.
 
xntrx said:
has anyone tried this for a sunroof? i wonder if its too much load. would be nice for my s70. also autoloc sells a kit for this, i read an install a couple years back in the foca (fiero owners club) magazine. would be nice to do a all switch, like on a4's where you can roll up all w/ the key.
well...my remote keyless entry system has a on-lock output that could be used with five auto-fucntion replays to roll up and close everything. I'd imagien most systems would... the other possibility is simply using the doorlock switch in the door to activate all locks and trigger the 5 relays. The windows would work well, but I'd imagien sunroof amperage draw will be significantly higher (and the differnt load size may interfere wiht the operation of the delay circuit). the other otopion is to use the delay relay to trigger antoerh high amperage relay, but then the load problem is even worse....
 
Yep - One quick "click", and the window rolls itself down (auto). If you hold the switch for more than about 1/2 second, the window stops when you release the switch (normal mode).

The relay is sensitive to the load, and I don't know how the sunroof motor compares to a window motor. For example, when I tested this setup with the engine off and battery slightly low, the window stopped once or twice (too soon) on its way down. It works perfectly with the engine running, though.

--Adam
 
aj164 said:
I did a search and didn't find this mentioned, so here it is:

Obtain :badboy: the auto-down relay from a Volvo 850. (located in the center console on the wiring that comes from the window switch cluster)

I have a lot relay from 850 T5-R... what color have relay?

Very Thanks!

Bye, Bruno!
 
Dad has one of the very last 940s, and this has auto-down as standard....but its VERY intermittant...it'll randomly stop on the way down. Knackered relay?

The 700/900 'leccy' systems are really quite retarded...my mates 93 vauxhall cavalier (middle-range family car...really not expensive at all!) has total closure on the key, and 'soft' electric windows, while Volvo were still using 'hard' switches in 98! And a relay to do auto-down...shouldn't be necessary. I even saw an early 90s Nissan Sunny with an 'all windows' control - one switch to work them all - very cool for hot days! And again, not an expensive car...

Still, one small triumph (for which I'll let them off the above sins!) - late 940 illuminated switches drop straight into the stock 360 (and presumably 740) wiring. Hurrah! Guess what's in the post...

cheers

James
 
xntrx said:
has anyone tried this for a sunroof? i wonder if its too much load. would be nice for my s70. also autoloc sells a kit for this, i read an install a couple years back in the foca (fiero owners club) magazine. would be nice to do a all switch, like on a4's where you can roll up all w/ the key.
My S70 (98 T5) sunroof was auto-open. Maybe yours is broken, or doesn't have it - in which case there might be a different relay to grab from another S70.
 
Sorry - no pics of the relay. It's installed behind the door panel, and I hope that panel doesn't have to come off anytime soon.

The relay is about 1" x 1" x 2" and it has four flat-blade conductors. If you open it up, you'll see a circuit board with an 8-pin DIP, a diode, and a board-mounted relay.

As far as I could tell, there was only one such relay on the 850 (at least the 850 I rummaged through). It's not conveniently located on the fuse panel or some other nice relay panel for you, it's actually part of the wiring harness that is attached to the window/mirror switch cluster. That wiring harness is soldered onto the switches, so you'll have to cut the relay off if you want to keep the relay socket.

If your factory auto-down in the 940 is doing strange things, it could be the relay, it could be the window motor, or it could be the window hardware. The relay is looking for a high current draw, which usually happens when the window hits the stop. If the motor draws too much current at other times (because the motor is bad or the window is dragging), the relay will shut it down. Also, I've noticed that it stops in the middle of travel if the battery voltage is low. So - if you have a bad connection, bad alternator, or bad battery... you got it.
 
In the seven(!) years since this was posted, has anyone done this to a 240? If so, maybe you could post up a clarification of the wiring. Actually, just saying which wires from the relay go to the wires coming out of which pin at the switch would be most helpful and idiot proof.

I have only red and black at the driver's switch and a few are doubled. The only ones that are completely clear to me are the ones going to the motor, but based on the original post here I'm not sure how to tap into this part (yes, I suck at electrics).
 
In the seven(!) years since this was posted, has anyone done this to a 240? If so, maybe you could post up a clarification of the wiring. Actually, just saying which wires from the relay go to the wires coming out of which pin at the switch would be most helpful and idiot proof.

I have only red and black at the driver's switch and a few are doubled. The only ones that are completely clear to me are the ones going to the motor, but based on the original post here I'm not sure how to tap into this part (yes, I suck at electrics).

You'll have to get a test light or meter and find which two wires are power in. Most likely, the power wires go to the middle of the window switch. I used to have a 260. The motor in the 240/260 might draw too much current and cause the 850 circuit to switch off before the window is all the way down. That is a guess; I never tried this on the 260.

-AJ
 
Back
Top