2010 Cadillac Truck SRX AWD V6-3.0L Page 1510
controls, snapshot, and plot functions can help detect erratic sensor response. To test the sensor signal under vacuum conditions, use the
Quick Snapshot and the Purge/Seal functions to capture data while commanding purge to 20 percent, then plot the data to look for erratic
sensor operation. A similar test can be done for the pressure side of the sensor operation by applying pressure with the J 41413-200 - EEST
while taking a snapshot.
Reference Information
Schematic Reference
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
Special Tools
J 41413-200 - Evaporative Emission System Tester (EEST)
Circuit/System Verification
1. Remove the fuel cap.
2. Ignition ON, engine OFF.
3. Observe the Fuel Tank Pressure Sensor parameter with a scan tool.
4. The Fuel Tank Pressure Sensor parameter should be 1.3-1.7 V.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the B150 fuel tank pressure sensor.
2. Ignition OFF, test for less than 5 ohm of resistance between the low reference circuit terminal 2 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.
3. Ignition ON, test for 4.8-5.2V between the 5V reference circuit terminal 3 and ground.
瀚慖f less than the specified range, test the 5V 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 5V reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
4. Verify the scan tool B150 fuel tank pressure sensor parameter is less than 0.2V.
瀚慖f greater than the specified range, test the signal circuit terminal 1 for a short to voltage. If the circuit tests normal, replace the K20 ECM.
5. Install a 3A fused jumper wire between the signal circuit terminal 1 and the 5V reference circuit terminal 3. Verify the scan tool fuel tank
pressure sensor parameter is greater than 4.7V.
瀚慖f less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the
K20 ECM.
6. If all circuits test normal, test or replace the B150 fuel tank pressure sensor.
