530t on a '76 corvette

I'm trying to get this installed in my '76 Corvette with my Viper 5704 system. Driver's door goes down fine, doesn't do well going up (maybe a centimeter at a time w/an obvious current draw from the system). Passenger doesn't do well either up or down (same idea as up on the driver's side). My wiring schematic is included. I'm not seeing anything I've done wrong, but that's why I'm here. Let me know your thoughts. Thanks.

Did you wire at the switches or at the actual motor wires. Also take ground and power supply directly to the battery using thicker wires. From that diagram if those switches really are 3 wire there's something missing like a pair of relays. Are they in with the motors? In which case you will need to open them up to get at the motors. This is the standard way to wire a window. AKA NEG at rest. NEG is fed to both motor wires. POS not connected. On "UP" POS is fed to "UP" motor wire and NEG STAYS connected to "DOWN" motor wire. On switching "DOWN" the reverse occurs, hence also known as a 5 wire or reversing polarity system. That diagram is either missing the grounds at the switches or missing 2 relays. Anyway the point is you must find and go to the actual motor wires.

Here is another diagram that I found for my car. Looks like the motors themselves are the ground. Does this help?

try and remove the grounds on the purple and PURPLE / black. not sure if the 530T will operate that way but the factory motor probably likes the opposite winding to be open circuit, not connected to ground. mark

Ween wrote: try and remove the grounds on the purple and PURPLE / black. not sure if the 530T will operate that way but the factory motor probably likes the opposite winding to be open circuit, not connected to ground. mark

Sounds like that would make sense. I'll have to give that a shot.

You're the man... Disconnected the violet and violet/black and it's working MUCH better. On to the next problem... Looks like it's a matter of resistance. I guess these older setups just aren't as efficient. I have the dip switches set to high resistance, yet the windows still won't move up or down without some help. I'm using the 530T wires at the factory length. It would be nice to not have to, but would cutting them any shorter help? Any ideas?

Q.) How did they work before the set-up?

https://www.the12volt.com/installbay/file.asp?ID=1069

Ween wrote: https://www.the12volt.com/installbay/file.asp?ID=1069

You beat me to it. That's exactly what I ended up doing last night and all is well. Everything works like a charm. Thanks a million for all of the help guys.