The following is a post I authored on another forum about how to convert non power folding mirrors (code DL8) to power folding mirrors (code DL3) in a 2007 Tahoe. These are the steps I undertook for converting a LT1 Tahoe to DL3 (power folding mirrors):
1. Purchase the following parts: LH DL3 mirror (# 15882682), RH DL3 mirror (# 15882683), Drivers Door Module (DDM) module (# 15093440). These mirrors come with black unpainted trim, but it is a simple matter to pop them off and swap with your painted originals.
2. Once you have the parts go ahead and install the mirrors and DDM. Instructions:
- Roll down the windows
- Disconnect the negative battery cable
- Removing the rectangular door lock button (gently pry up the small tab and the button will lift off)
- Remove the triangle trim (pop the clips from the top first and swing down to lift off the bottom tab)
- Remove the DDM & PDM switch modules (gently pry up one end at a time - 2 clips hold the module in place)
- Remove the trim covers to expose the 10mm bolts behind the door release handle (1 bolt) and door pull handle (2 bolts)
- Remove the door trim panel by pulling around the perimeter to pop loose the retaining clips
- Remove the 3 nylon push in wire harness retainers (I used a nail puller wrapped in masking tape to keep from scratching the door frame)
- Remove the 3 10mm nuts holding the mirror (it won't fall because there is a pop clip on the top of the mirror housing holding it on)
3. At this point you simply reverse the process
3.5 - You will need to trim the bezel for the new DDM where the additional switch for mirror fold/open is located
4. Once the new mirrors are installed the new DDM will only work in local mode (i.e., it won't put anything out on the data bus so the only thing that it will do is operate the local drivers door window) This means that it will not operate any mirror functions, the other 3 windows will not operate, the drivers power door lock will not function, and the system won't recognize the drivers door opening/closing (so when you exit the vehicle your radio will remain on for ~ 10 minutes until it times out) This is normal.
5. At this point you need to have the DDM and the PDM (Passenger Door Switch Module) flashed via Tech 2 through the Service Provisioning System (SPS). This is the uplink from the dealer's Tech 2 interface unit that is attached to your vehicles OBD port that communicates with the GM database to pull the code for the downlink to your specific vehicle module.
6. Once flashed, everything should operate normally.
7. Also, if you want to use the park tilt function then you need to flash the Driver Information Console module as well. This will only be possible if your vehicle has the memory seats (8 way power option) as the mirror memory settings are stored in that memory module.
