Circuit Description
WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) supplies a 5-volt reference and a low reference circuit to both the Throttle Position (TP) sensor and the Manifold Absolute Pressure (MAP) sensor. The TP sensor sends a voltage signal back to the PCM relative to the throttle plate opening and the MAP sensor sends a voltage signal back to the PCM relative to the intake manifold pressure. The PCM can detect if the TP sensor or the MAP sensor are out of range by comparing the two values against the high and low limits and engine speed defined within the engine calibration. If the TP or MAP is not within the expected limits of the engine calibration, DTC P0105 is set.