Circuit/System Verification

WARNING: This page is about a different car, the 2018 Chevrolet Suburban 3500 HD. However, it is still accessible from the selected car via links, so may be relevant.

Ignition - On/Vehicle - In Service Mode
Verify DTC P0641, P0651 is not set.
- If the DTC is set
  Refer to Diagnostic Trouble Code (DTC) List - Vehicle
- Go to next step: If the DTC is not set
Engine - Running
Verify DTC P0336 is not set.
- If the DTC is set
  Refer to Circuit/System Testing below
- Go to next step: If the DTC is not set
Verify the scan tool parameter: Crankshaft Position Active Counter = Increments
- If the parameter value does not increment
  Refer to Circuit/System Testing below
- Go to next step: If the parameter value increments
Verify the scan tool parameter: Crankshaft Position Resync Counter = 0 Counts - The engine should not stumble/stall.
Perform the action while monitoring the parameter:
- Wiggle the harness and connector: B26 Crankshaft Position Sensor
- Wiggle the harness and connector: K20 Engine Control Module
- If greater than 0 counts
  Repair as necessary - Wiring/Terminal(s)/Electrical Connector(s)
- Go to next step: If 0 counts
Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Verify the DTC does not set.
- If the DTC sets
  Refer to Circuit/System Testing below
- Go to next step: If the DTC is not set
All OK.