Installing Power Winows,locks And Mirrors

FrankGMC · January 25, 2009

I have a GMC sierra 2500 HD classic 2007. stripped with no power window, door, locks or mirrors. I purchased the doors from a 2004 chevy silverardo 2500 with power windows,locks and mirrors. I put the guts of these power items from the silverado into my sierra. Do I need relays? do I have to replace the fuse box? What do I have to do to power them or can it even be done? I ordered the truck with out power accessories. Would the doors come with the plug in even though I didnt order the doors that way? your help with this would be greatly appreciated.

digicom1 · April 23, 2009

from some who recently did do it you will need the body wire haness from a truck with power windows along with the fuse block on the a piler and the one down by your left foot also you will need to run a wire from main fuse block under hood to the fuse block by foot. also you will need to connect accessory volt from bcm to lower harness

bill190 · April 24, 2009

Sure you can do whatever you want!

I've not seen much of any extra wiring on GM vehicles for options which did not come with the vehicle. So probably not existing wiring, but might check anyway.

To know if you have the wiring, fuses, etc. You would need a factory wiring diagram and need to do a lot of hunting around.

I would suggest adding a relay and your own fuse to power these things. You would still need a factory wiring diagram to do it right though.

Doing it right would be that you don't overload existing circuits, and have the proper fuse protection for the wiring in the doors. Then you will not have a problem with fuses blowing.

The problem with automotive stuff is nothing is marked for how much amperage it uses!

So get a 50 amp ammeter, run the mirror and see how much amperage it draws. Same with windows and door locks.

(If you use a 10 amp ammeter to measure more than 10 amps, you will ruin it.)

Use the same size wiring as is used in the door or larger.

Here are wire sizes and amperage...

Gauge 12V

22 - 5A

20 - 8A

18 - 10A

16 - 20A

14 - 40A

12 - 60A

10 - 100A

8 - 150A

Wire sizes conversion...

Metric AWG

0.5 - 20

0.8 - 18

1.0 - 16

2.0 - 14

3.0 - 12

5.0 - 10

8.0 - 8

Then the reason for the relay would be so you don't overload any existing circuits. The relay uses very little power, so it can be added to an existing "ignition on" circuit and not blow the fuse for that circuit. You would be best to use a factory wiring diagram to find an appropriate circuit and wire to tie into for this. Then you won't be connecting to "just anything" and will avoid future problems.

A relay is just an electric switch. Wire the contacts to power your doors. Wire this directly to battery power, but with a fuse of the appropriate size (depending on the wire size you use and the amperage draw of the stuff in the door.)

Hint: It is unlikely you would have the mirror moving, and the door locks activating, and all power windows moving - all at the same time. So say the largest power user is the power windows (I don't know), you could probably get away with running a wire size and fuse with enough power to operate all windows at the same time (people sometimes roll all windows down at the same time on a hot day) and not need to provide enough amperage to power "everything" on all at once.

The relay should say "continuous duty" on it and these get can get HOT. So best to mount it in the engine compartment where air will blow on it. The relay should operate on 12 volts DC and the contacts rated to handle the amperage of your circuit or more. An RV business which sells trailer wiring would probably know what a continuous duty relay was as opposed to an auto parts store which just knows part numbers. Some relays like starter relays are not designed to be on all the time and will burn out.

How relays work...

http://electronics.howstuffworks.com/relay.htm

How to use an ammeter

http://scienceshareware.com/how-to-measure...-with-a-dmm.htm

Factory wiring and service manuals...

http://www.helminc.com