2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1088
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
1. Verify that the engine coolant level is correct.
瀚慖f the engine coolant is not at the correct level, refer to Loss of Coolant (See: Engine, Cooling and Exhaust/Cooling System/Testing and
Inspection/Symptom Related Diagnostic Procedures/Loss of Coolant).
2. Verify that the engine coolant temperature is at the normal operating temperature.
瀚慖f the engine coolant temperature is colder than the normal operating temperature, refer to Thermostat Diagnosis (See: Engine, Cooling
and Exhaust/Cooling System/Testing and Inspection/Symptom Related Diagnostic Procedures/Thermostat Diagnosis).
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the
conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the B34 ECT sensor.
Caution: Do NOT use a test lamp to test the continuity of the circuit. Damage to the control module may occur due to excessive current
draw.
Note: The control module or the sensor may be damaged if the circuit is shorted to battery positive voltage.
2. Test for less than 5 ohm between the low reference circuit terminal 2 and ground.
瀚慖f greater than specified value, test the circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20
ECM.
3. Ignition ON, observe the scan tool the ECT sensor parameter. Verify that the ECT sensor parameter is at -40掳C (-40掳F).
瀚慖f warmer than the specified value, test the signal circuit for a short to ground. If the circuit/connections test normal, replace the K20
ECM.
Note: If the fuse in the jumper wire opens, the signal circuit is shorted to a voltage and the ECT sensor may be damaged.
4. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool ECT sensor
parameter is warmer than 142掳C (288掳F).
瀚慖f colder than the specified value, test the signal circuit for an open/high resistance or for a short to voltage. If the circuit/connections test
normal, replace the K20 ECM.
5. If all circuits test normal, test or replace the B34 ECT sensor.
Component Testing
1. Ignition OFF, disconnect the harness connector at the B34 ECT sensor.
Note: A thermometer can be used to test the sensor off the vehicle.
2. Test the ECT sensor by varying the sensor temperature while monitoring the sensor resistance. Compare the readings with the Temperature
Versus Resistance - Engine Coolant Temperature Sensor (See: Powertrain Management/Computers and Control
Systems/Specifications/Temperature Versus Resistance - Engine Coolant Temperature Sensor) table and verify that the resistance is within 5
% of the specification.
瀚慖f not within the specified range, replace the B34 ECT sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Engine Coolant Temperature Sensor Replacement (LF1) (See: Engine, Cooling and Exhaust/Cooling System/Engine - Coolant Temperature
Sensor/Switch/Coolant Temperature Sensor/Switch (For Computer)/Service and Repair)Engine Coolant Temperature Sensor Replacement
(LAU) (See: Engine, Cooling and Exhaust/Cooling System/Engine - Coolant Temperature Sensor/Switch/Coolant Temperature
Sensor/Switch (For Computer)/Service and Repair)
