2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1477
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 Testing
1. Ignition OFF, disconnect the KR27 starter relay.
2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 10 Ohms between the relay
ground circuit terminal 85 and ground.
瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 30 and ground.
瀚慖f the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
瀚慖f the circuit tests normal and the B+ circuit fuse is open, test the control circuit terminal 87 for a short to ground.
4. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
瀚慖f the test lamp illuminates, test the control circuit for a short to voltage.
5. Parking brake applied and the transmission is in NEUTRAL or PARK. Momentarily install a 30 A fused jumper wire between the B+ circuit
terminal 30 and the control circuit terminal 87. Verify the starter is activated.
瀚慖f the starter does not activate, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the starter.
6. Ignition OFF, connect a test lamp between the control circuit terminal 86 and the ground circuit terminal 85.
7. Transmission in park or neutral, cycle the ignition between the OFF and CRANK position. The test lamp should turn ON and OFF when
changing between the selected states.
瀚慖f the test lamp is always ON, test the control circuit for short to voltage. If the circuit tests normal, replace the K20 ECM.
瀚慖f the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace
the K20 ECM.
8. If all circuits tests normal, replace the KR27 starter relay.
Component Testing
Relay Test
1. Ignition OFF, disconnect the starter relay.
2. Test for 60-180 Ohms between terminals 85 and 86.
瀚慖f not within the specified range, replace the relay.
3. Test for infinite resistance between the following terminals:
* 30 and 86
* 30 and 87
* 30 and 85
* 85 and 87
瀚慖f not the specified value, replace the relay.
4. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for
less than 2 Ohms between terminals 30 and 87.
瀚慖f greater than specified range, replace the relay.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
