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About electronic parts install

received my master control box (all windows) today, I’d like to know the protocol for installation

Last week when I removed the other part because it wasn’t working properly, two days later I decided to reconnect it, to my surprise just as the part closed in about 1/4" from the connector the only window that was down started to go up – the connector was not put together [ it was magic (smile)] At that point I figure I’d just do it again to get the window all the way up then wait for the replacement part.

Now that the part has arrived my question is, should I disconnect the car battery before connecting the replacement part.

Also, why did the window go up when the connection wasn’t actually made?

It’s probably a good idea to disconnect the battery if you don’t have a lot of experience with electrical and mechanical parts. Some vehicles are wired parallel, series and series parallel for power windows. When I was working on my wife’s Olds a couple of years ago…the windows would go up when I disconnected the main window switch. A bad switch on the driver’s side can kill a window on the passenger side and vice versa. It’s not magic it’s just the way the windows are wired. It’s probably a default function of your power windows.

Perhaps the windows are supposed to go “up” as a default setting when there is a wiring problem. I think pulling the ground (negative battery post) off the battery is a good idea, just in case. You might also pull the fuses for the power windows, but I think disconnecting the battery is best.

“You might also pull the fuses for the power windows, but I think disconnecting the battery is best.”

+1

There’s less chance of an error this way. If you have to use a code to get the radio to work after disconnecting the power, it might make sense to pull the fuses.

I always disconnect the battery before doing any electrical work on my cars. I just disconnect the negative battery connection. There’s a risk of damaging the ECM/BCM if you don’t. On newer cars however, there are downsides to disconnecting the battery, as you loose various programming you or the car’s ECM has done, which might be a motivation to just pull the fuses for that particular circuit.

Wow, I was just about to install the part (without battery disconnect), but remembered my post and came back in to check the pro info. Thanks, I’ll disconnect the battery

I’d disconnect the battery before working on it. You can get some damaging surges when inserting and removing electrical connectors on certain equipment. Some electronics are continuously powered on your car, even with the ignition off.

It’s possible that your window went up either as a coincidence, or you may have had enough of a static charge on your hands or on the connector you were about to insert to trigger a solid-state controller that at that point was just “floating” with no connection to it–some semiconductor switches and logic circuits act like an antenna if they are left hanging between ground and positive voltage–they then become sensitive to any slight change one way or the other. No doubt one of the pins on the connector you were about to insert provided a positive or ground “reference” to keep this type of situation from happening, and without it connected, you can get the results you experienced.

If the window went up by “magic” then the control box is not the problem…I would be looking for a short in the wire bundle you were handling when the window went up…

Ohhhhhhh Caddyman I sincerely hope that isn’t the problem. I received the new part tested it and it seems to work fine, but I have not installed it permanently yet, I waiting on some door clips before final install.

@ oblivion when I read this: “or you may have had enough of a static charge on your hands or on the connector you were about to insert to trigger a solid-state controller that at that point was just “floating” with no connection to it–some semiconductor switches and logic circuits act like an antenna if they are left hanging between ground and positive voltage–they then become sensitive to any slight change one way or the other… you can get the results you experienced.” it really sounds like you hit the nail on the head.

Thank you and everyone else for the info.