Circuit/System Verification

• Incorrect fluid level or condition - Coolant @ Surge Tank - Refer to: Loss of Coolant (LSY) , or Loss of Coolant (LGY) 
• G8 Engine Coolant Pump - Auxiliary - Abnormal noise /Leaking/Loose Clamps/Visible Damage
NOTE:

If the system has recently been serviced, it is possible that air is trapped in the system causing the condition or a DTC to set.

• Air Pocket @ Cooling System - Refer to: Cooling System Draining and Filling (LSY GE 47716) , or Cooling System Draining and Filling (LSY Static Fill) , or Cooling System Draining and Filling (LGY Static Fill) , or Cooling System Draining and Filling (LGY GE 47716)
• Antifreeze Concentration - Incorrect - Refer to: Cooling System Draining and Filling (LSY GE 47716) , or Cooling System Draining and Filling (LSY Static Fill) , or Cooling System Draining and Filling (LGY Static Fill) , or Cooling System Draining and Filling (LGY GE 47716)
• Hoses / Lines @ Cooling System - Kinked/Leaking/Restricted/Visible Damage
• Hoses / Lines @ G8 Engine Coolant Pump - Auxiliary - Kinked/Leaking/Restricted/Visible Damage

• If a condition exists 

  Repair or replace as necessary

• Go to next step: If no condition exists 

• If DTC U137E is set and no other DTCs are set 

  Replace the component: G8 Engine Coolant Pump - Auxiliary

• Go to next step: If the DTC is not set 

• If DTC U0623 is set and no other DTCs are set 

  Refer to: Circuit/System Testing

• If DTC U0623, U1345 is set and other DTCs are set 

  Refer to: DTC U1345-U1349

• Go to next step: If none of the DTCs are set 

• If any of the DTCs are set 

  Replace the component: G8 Engine Coolant Pump - Auxiliary

• Go to next step: If none of the DTCs are set 

Verify the scan tool parameter:

• Auxiliary Coolant Pump Internal Status = Okay
• Auxiliary Coolant Pump Stalled = No

• If not the specified state 

  Replace the component: G8 Engine Coolant Pump - Auxiliary

• Go to next step: If the specified state 

• If not equal 

  Refer to: Circuit/System Testing

• Go to next step: If equal 

• If not the specified state 

  Refer to: Circuit/System Testing

• Go to next step: If the specified state 

• If not the specified state 

1. Ignition/Vehicle - Off
2. Perform the following procedure/test: Cooling System Leak Testing 

   Verify the procedure/test passes.

   • If the procedure/test does not pass - Repair or replace as necessary
   • Go to next step: If the procedure/test passes
3. Replace the component: G8 Engine Coolant Pump - Auxiliary

• Go to next step: If the specified state 

Verify a condition does not exist with the component: G8 Engine Coolant Pump - Auxiliary - Turns Off

Perform the action while monitoring the component:

• Wiggle the harness and connector: G8 Engine Coolant Pump - Auxiliary
• Wiggle the harness and connector: K20 Engine Control Module

• If a condition exists 

  Repair as necessary - Wiring / Terminal(s) / Electrical Connector(s)

• Go to next step: If no condition exists 

Verify the DTC does not set.

• If the DTC sets 

  Refer to: Circuit/System Testing

• Go to next step: If the DTC is not set