Circuit/System Description

WARNING: This page is about a different car, the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

The transfer case incremental position sensor (IPS) and the transfer case rotational position sensor (RPS) both send current transfer case mode/range position to the transfer case shift control module (TCCM). Both sensors send this information as voltage signals which are converted to degrees and rotational direction by the TCCM software. If the two sensors disagree by greater than a predetermined amount, the DTC will set.

The IPS receives an 8 volt reference signal from the TCCM and sends back a transfer case incremental position signal and an encoder rotational direction signal.

The RPS (also known as the transfer case two/four wheel drive actuator position sensor) receives a 5 volt reference signal from the TCCM and sends back a continuously variable pulse width modulated signal to the TCCM. This continuously variable signal indicates the position of the transfer case actuator.

The IPS is more sensitive than the RPS, but needs to reference the RPS value at key-up and mode changes. The RPS is an absolute sensor. The TCCM syncs the IPS with the RPS at key-up and mode changes.

The IPS is an integral part of the transfer case actuator and cannot be replaced independently.

The RPS is an independently replaceable part.