2010 Cadillac CTS Sedan AWD V6-3.6L Page 1058
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)
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
(LLT) (See: Engine, Cooling and Exhaust/Cooling System/Engine - Coolant Temperature Sensor/Switch/Coolant Temperature
Sensor/Switch (For Computer)/Service and Repair)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, setup, and programming
P0130
DTC P0130 or P0150 (with LLT)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0130
- HO2S Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 1
DTC P0150
- HO2S Signal Circuit Shorted to Heater Circuit Bank 2 Sensor 1
Circuit Description
The engine control module (ECM) supplies a voltage near 450 mV between the heated oxygen sensor (HO2S) signal circuit and the low reference
