True TRD?

So I just bought my truck it's a 2001 trd off road double cab. But in place of the RR diff lock switch is the led light for the aftermarket alarm that came with it. I took off the plastic underneath the dash but couldn't find the 4wd computer but I saw the wires for it. It still engages into 4wd with the push button with no problem at all. What's going on?

 

The rear locker is not part of the 4WD system. The rear locker also comes on the 2WD Off Road TRD, afterall...

No rear locker, then it is not an Off Road TRD. My first Tacoma was a 2001 4WD TRD extra cab.

The locker is attached to the differential (above on one side of it)... so you can get under your truck and see if there is an e-locker attached to the pumpkin.