2010 Cadillac Truck SRX FWD V6-3.0L Page 1324
Circuit/System Testing
1. Verify the integrity of the entire air induction system including all turbocharger components by inspecting for the following conditions:
* Any damaged components
* Intake air pressure and temperature sensor damage
* A buildup of contamination, snow or ice at the BARO port on the ECM
* Loose or improper installation
* An air flow restriction
* Any vacuum leak
* Any type of air leak between the turbocharger and the throttle body
* An exhaust leak
瀚慖f a condition is found, repair as necessary.
2. Ignition OFF, disconnect the harness connector at the B65 intake air pressure and temperature sensor.
3. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 ohm
between the low reference circuit terminal 1 and ground.
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20
ECM.
4. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 3 and ground.
瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal,
replace the K20 ECM.
瀚慖f greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
5. Verify the scan tool Boost Pressure Sensor parameter is greater than 250 kPa (36.3 psi).
瀚慖f less than the specified range, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K20 ECM.
6. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the low reference circuit terminal 1. Verify the scan tool Boost
Pressure Sensor parameter is less than 1 kPa (0.15 psi).
瀚慖f greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal,
replace the K20 ECM.
7. If the circuits test normal, test or replace the B65 intake air pressure and temperature sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Turbocharger Pressure Sensor Replacement () for intake air pressure and temperature sensor replacement
* Control Module References (See: Testing and Inspection/Programming and Relearning) for engine control module replacement, setup, and
programming
P0237
DTC P0236, P0237, or P0238
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 P0236
- Turbocharger Boost System Performance
DTC P0237
- Turbocharger Boost Sensor Circuit Low Voltage
