* Transmission Control Module (TCM): This is the "brain" of the system. In a 1996 Blazer, the TCM's location is most commonly inside the vehicle, typically under the dash or center console area. It's a small, black box and may be difficult to find without a wiring diagram. It's not always easily accessible without removing some interior panels.
* Transmission Range Sensor (PRNDL): This sensor, also known as the Park/Neutral Position Switch (PNPS), is located on the transmission itself. It sends signals to the TCM indicating the gear selected by the driver.
* Various sensors on the transmission: These include things like the speed sensor and potentially others depending on the transmission type (4L60E is common for this year). These sensors are located on the transmission case and provide the TCM with crucial data about the transmission's operation.
* Wiring harness: The wiring harness connects all these components to the TCM and the vehicle's main computer system (PCM). The harness runs throughout the vehicle.
To find the TCM: Your best bet is to consult a 1996 Chevy Blazer repair manual or a wiring diagram specific to your vehicle. These resources will show the exact location and pinpoint the TCM among other components under the dash. Searching online for a wiring diagram for your specific Blazer (specify engine and transmission) might help you find a diagram.
Without a repair manual or diagram, attempting to locate the TCM blindly will be difficult and potentially damaging. If you're not comfortable working on your vehicle's electrical system, it's best to take it to a qualified mechanic.
