2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1928
The ECM detects that the ECT decreases less than 2 掳C (4 掳F) within 60 seconds. The condition exists for 4 S or a cumulative of 30 S.
P2602
The ECM detects the pump control circuit is shorted to ground. The condition exists for 4 seconds or a cumulative of 30 seconds.
P2603
The ECM detects the pump control circuit is shorted to voltage. The condition exists for 4 seconds or a cumulative of 30 seconds.
Action Taken When the DTC Sets
The DTCs are Type C DTCs.
Conditions for Clearing the DTC
The DTCs are Type C DTCs.
Diagnostic Aids
* This diagnostic uses a comprehensive approach to the diagnosis of the KR31 auxiliary coolant pump relay and its related circuits. The
auxiliary coolant pump relay is a printed circuit board (PCB) relay. The relay is an integral component to the underhood bussed electrical
center (UBEC). It cannot be removed and it is not visible.
* Much of the diagnosis is performed at the ECM connectors. Great care should be taken to ensure that the correct terminals are tested and the
proper test probes are utilized when performing this diagnostic.
* The test lamp is used to provide a visual aid to observe the integrity of the KR31 relay, the UBEC and the relay control circuit.
* Grounding terminal X2-58 activates the powertrain relay, which will supply power through KR31 relay coil and the relay control circuit.
Under normal circumstances the test lamp will illuminate with dim intensity due to the load created by the KR31 relay coil. If the test lamp
does not illuminate, or illuminates brightly a condition exists in the KR31 relay control circuit or the UBEC.
Reference Information
Schematic Reference
* Engine Cooling Schematics (See: Engine, Cooling and Exhaust/Cooling System/Diagrams)
* Engine Controls Schematics (LAU) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls
Schematics (LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
1. Ignition ON, verify that DTC P0480, P0691, or P0692, is not set.
瀚慖f a DTC is set, refer to DTC P0480, P0691, or P0692 (without/LF1) (See: P Code Charts/P0480) for further diagnosis.
Note: There is a slight delay before the cooling fan activates and reaches full speed.
2. Command the cooling fan ON from 20-90 % with a scan tool. Verify that the cooling fan turns ON and operates as commanded.
