2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2235
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)
* Probing Electrical Connectors (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Circuit Testing/Probing Electrical Connectors)
* Electrical Center Identification Views (See: Maintenance/Fuses and Circuit Breakers/Fuse/Application and ID)
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 35616 GM-Approved Terminal Test Kit
* J 43244 Relay Puller Pliers
Circuit/System Verification
1. Ignition ON, engine OFF, command the powertrain relay ON and OFF, with a scan tool, while observing the following powertrain relay coil
control circuit status parameters.
* Powertrain relay coil control Ckt. Short Gnd Test Status
* Powertrain relay coil control Ckt. Open Test Status
* Powertrain relay coil control Ckt. Short Volts Test Status
Each parameter should toggle between OK and Not Run or Not Run and OK
2. Ignition ON, observe the DTC information with a scan tool. DTC P0685, P0689 or P0690 should not set.
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed
from the Freeze Frame/Failure Records data.
Circuit/System Testing
Note: You must perform the Circuit/System Verification first.
1. Ignition OFF, disconnect the KR75 powertrain relay.
2. Verify a test lamp illuminates between both of the following relay battery voltage circuit terminals and ground:
* Terminal 85
* Terminal 30
瀚慖f the test lamp does not illuminate, test the relay battery voltage circuit for an open/high resistance or a short to ground.
Note: The ignition voltage circuit is between the powertrain relay and the ECM. The ignition voltage is a feedback circuit.
3. Ignition OFF, verify that a test lamp does not illuminate between the ignition voltage circuit terminal 87 and ground.
瀚慖f the test lamp illuminates, test the ignition voltage circuit for a short to voltage.
4. Connect a 20 A fused jumper wire between the relay switch B+ circuit terminal 30 and the relay switch ignition voltage circuit terminal 87.
5. Ignition ON, observe the scan tool EC Ignition Relay Feedback Signal parameter. The ECM should communicate, and the parameter should
display 9-14 V.
瀚慖f not the specified range, or the ECM does not communicate, test the ignition voltage circuit between the powertrain relay and the ECM
for a short to ground or for an open/high resistance. If the circuit/connections test normal, replace the K20 ECM.
6. Ignition OFF, verify that a test lamp does not illuminate between the control circuit terminal 86 and B+.
瀚慖f the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.
7. Connect a DMM set to the diode setting between the control circuit terminal 86 and ground.
8. Ignition ON, verify the DMM does not display OL.
瀚慖f the DMM displays OL, test the control circuit for a short to voltage, or an open/high resistance. If the circuit tests normal, replace the
K20 ECM.
9. If all circuits test normal, replace the KR75 powertrain relay.
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