Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector for all position sensors connected to the 5-volt reference circuit.
- Ignition ON, observe all scan tool Driver Position Module sensor parameters for Seat 1 and Adj. Pedals Info. The readings should be 0.0 volts.
- If greater than the specified value, test the appropriate signal circuit listed below for a short to voltage. If the circuit tests normal, replace the MSM.
- Horizontal position sensor terminal 3 X2
- Front vertical position sensor terminal 1 X2
- Rear vertical position sensor terminal 5 X2
- Recline position sensor terminal 2
- Lumbar horizontal position sensor terminal D X2
- Lumbar vertical position sensor terminal B X2
- Adjustable pedal position sensor terminal 1
- If greater than the specified value, test the appropriate signal circuit listed below for a short to voltage. If the circuit tests normal, replace the MSM.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit at any one of the position sensors and ground.
- If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
- If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Connect each position sensor one at a time and verify that the DTC does not set as current.
- If the DTC sets as current, replace the appropriate position sensor.
- If all circuits test normal, replace the MSM.