Hello just looking for some help on how to swap my speedometer input. A little background; I have a 2005 Cobalt base model with a 2.2, factory it had no options, no power windows, locks, and etc
I swapped out the doors with a wrecked car that had power windows, locks and mirrors, heated seats but even after I wired it all nothing would work but the mirrors and the seats. I swapped the bms from the parts car and everything worked, except the car now wouldn't start due to the security system.
I ended up getting a dealer to flash the bms from the parts car so it would work with my balt but now my speedometer does not work. From what I have read the base models get the input from a speed sensor in the transmission while the fully loaded models get the input from the abs sensors. The car must still be reading the sensor I the transmission because my odemeter is still working correctly but the speedo doesn't read at all. Hoping someone can give me some insight on swapping the input signal, I'm sure I'll probably need a dealer but if I can tell them what needs to be done it will make dealing with them a lot easier. Thanks