2010 Cadillac Truck SRX FWD V6-3.0L Page 1653

2010 Cadillac Truck SRX FWD V6-3.0L Page 1653

2. Ignition ON, verify a test lamp illuminates between both of the following relay battery voltage circuit terminals and ground.

* Terminal 86

* Terminal 87

瀚慖f the test lamp does not illuminate, test the relay battery voltage circuit for a short to ground or an open/high resistance.

Note: The ignition voltage circuit is between the powertrain relay and the ECM. The ignition voltage circuit is a feedback circuit.

3. Ignition OFF, verify that a test lamp does not illuminate between the ignition voltage circuit terminal 30 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 87 and the relay switch ignition voltage circuit terminal 30.

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 85 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 85 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.

Component Testing

Note: Depending on the application, the relay coil resistance will be within one of the following ranges.

1. Test for one of the following resistance specifications between terminals 85 and 86 of the KR75 powertrain relay:

* 70-110 ohm

* 200-250 ohm

瀚慖f not within the specified range, replace the KR75 powertrain relay.

2. Test for infinite resistance between the following terminals of the KR75 powertrain relay:

* 30 and 86

* 30 and 87

* 30 and 85

* 85 and 87

瀚慖f not the specified value, replace the KR75 powertrain relay.

3. 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 ohm between terminals 30 and 87.

瀚慖f greater than the specified range, replace the KR75 powertrain relay.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Relay Replacement (Attached to Wire Harness) (See: Power and Ground Distribution/Power Distribution Relay/Service and Repair/Relay

Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (See: Power and Ground Distribution/Power

Distribution Relay/Service and Repair/Relay Replacement (Within an Electrical Center))

* Control Module References (See: Testing and Inspection/Programming and Relearning) for K20 ECM replacement, setup, and

programming

P0690

DTC P0685 or P0690 (LF1)