Need help with Electric windows Relay diagram.

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Need help with Electric windows Relay diagram.

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Hi there,

I've installed Spal electric windows kit on the back doors using stock electric window buttons on my Fiat Panda. I made molds for buttons out of tweeter covers and wrapped them in leather to match interior. Now, I used (as I think same method) to wire up buttons through set of 2 relays to reverse polarity to drive electric motor here is the diagram of how I wired each door.




The button operates each relay in turn when u press UP or DOWN and LED is on but when I hook clean 12 volt to pin 87, fuse blows as soon as I touch it. Can any one spot where I'm going wrong.

Button 4 pins. 12v pin for LED, Common and 2 pins Up and DOWN of the Common.

I wired in a way so that the motor never had 12v, so that relays operated by ground. But its not working as it keep blowing the fuse each time pin 87 is live. Though maybe repays were faulty so I swapped them but it still does the same. I'm suing standard 12v DC 30/40A relays btw.

Please help as I'm stuck!!! :bang:
 
See this.

I think you've confused the trigger and switch sides of the relay, but it's late..............

If the cover is plastic you can pop it off, test with a multimeter to see which is which. Anyroadup, the switching side should show resistance when the terminals are connected through an ohmeter, the power side open circuit (no resistance). If still in doubt, construct a mock up with a battery and a 12v bulb.
 
That doesnt make any sense to hook power from the battery to pin 30.
unless its going to be some sort of 4 relay circuit. Here is the better diagram of how I have wired relays.

 
That doesnt make any sense to hook power from the battery to pin 30.
unless its going to be some sort of 4 relay circuit. Here is the better diagram of how I have wired relays.


I'm not sure what the light green wire represents. The coil side of the relays (85 & 86 on your diagram) require + and -, which should be switched (doesn't really matter which side, but a live with ignition would probably suit best). Only one side of the switched side of the relay 87 or 87A needs a contact. It doesn't matter if 30 is used as the contact or either 87 or 87a.

And see this.

I'd not use the feed from the battery as a loop in to the switch and switched side. The loads on each are very different, they need different fuse values.

As I say, if confused, do a mock up with 12v bulbs. Get it wrong on the car and you risk a fire.
 
I'm not sure what the light green wire represents. The coil side of the relays (85 & 86 on your diagram) require + and -, which should be switched (doesn't really matter which side, but a live with ignition would probably suit best). Only one side of the switched side of the relay 87 or 87A needs a contact. It doesn't matter if 30 is used as the contact or either 87 or 87a.

And see this.

I'd not use the feed from the battery as a loop in to the switch and switched side. The loads on each are very different, they need different fuse values.

As I say, if confused, do a mock up with 12v bulbs. Get it wrong on the car and you risk a fire.


As I mentioned originally. I wired in a safe way so the motors both cables are always Grounded. Light green cable is a switch wire to providing ground for a 85/86 coil. So both 30's are always have ground until I hit the UP or DOWN switch. Which is always Com/Open (open ground) and when I hit UP or DOWN it Com/Close the ground (light green) providing ground to other relay 1 or 2, operating relay coils on those relays making other pin 30 on relay 1 live or pin 30 on relay 2 live making the polarity switch.

All tested and working up to the point untill I connect clean 12 volt to any of the pin 87. Then it blows the fuse. So if I take the link from pins 87 it all works again. But I need 87 to provide 12 volt to the motor as both cables are grounded.
 
and again the link makes no sense as it still showing pin 30 with 12 volt on it. If I connect 12 volt to 30 then the motor has to go to pin 87 or 87A since it cant be 85 or 86 since its a operating coil. And it cant go to 87A coz then both cable on the motor would have 12volt and I ll have to replace the motor very soon if I wire it that way besides if pin 30 is life that only means that relay can only provide 12 volts to 87A or 87 but no ground which I need to have a reverse polarity.
 
I'm pretty sure my diagram is correct but I just need to up my cable to 12AWG and separate coil feed and motor feed. Use 16AWG to feed coil and 12AWG to feed motor side (pin 87). Try that if it works. Coz by just splitting up relays it works, drives motor up but once I link second relay for polarity switch it trips. I recon cable too small and builds resistance up to a point where it trips. Will see in few days once the cable arrives.
 
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