Circuit/System Verification

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, 2018 Chevrolet Suburban, and 2018 Cadillac Escalade ESV. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The audible clicking intensity will vary depending on mounting locations and interference with the fuel injectors clicking. You may also feel a change in the frequency of clicking.

Ignition ON.
Verify the EVAP Purge Solenoid Valve control circuit status parameters while commanding the solenoid from 0% to 50% and back to 0% with a scan tool:
- EVAP Purge Solenoid Valve Control Circuit Open Test Status
- EVAP Purge Solenoid Valve Control Circuit Low Voltage Test Status
- EVAP Purge Solenoid Valve Control Circuit High Voltage Test Status
- If Malfunction is displayed
  Refer to Circuit/System Testing below.
- Go to next step: If Malfunction is not displayed
Verify the EVAP Purge Solenoid Valve Control Circuit parameters above do not display Malfunction when moving the related harnesses and connectors of the Q12 Evaporative Emission Purge Solenoid Valve.
- If Malfunction is displayed
  Refer to Circuit/System Testing below.
- Go to next step: If Malfunction is not displayed
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 does not set
All OK.