2010 Cadillac Truck SRX FWD V6-3.0L Page 1999
Note: A low battery voltage or charging system condition may cause a DTC to set.
1. Ignition ON, observe the DTC information with a scan tool. DTC P0121, P0122, P0123, P0222, P0223, P0562, P0621, P0622, or P2135
should not set.
瀚慖f a DTC sets, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble
Code (DTC) List - Vehicle) for further diagnosis.
2. Clear the DTCs with a scan tool. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power
down.
3. Ignition ON, observe the scan tool TAC Motor parameter. The reading should display Enabled.
4. Observe the DTC information with a scan tool. DTC P1516, P2101, P2119, or P2176 should not set.
Note: If there is a condition with the throttle body, the TAC Motor Command parameter will go to 99 % for a predetermined amount of time
and then a DTC sets. Once a DTC is set, the TAC Motor Command parameter will go to 0 % and the TAC Motor parameter will display
Disabled.
5. Perform the scan tool Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should
display Enabled while the Throttle Sweep Test is in progress.
Note: Before replacing the throttle body assembly, make sure the TAC motor control circuits are not shorted to B+.
瀚慖f not the specified value, replace the throttle body assembly.
6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the
conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
Warning
Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.
1. Ignition OFF, verify the following conditions do not exist with the Q38 throttle body assembly:
* A throttle blade that is not in the rest position
* A throttle blade that is binding open or closed
* A throttle blade that is free to move open or closed without spring pressure
瀚慖f a condition is found, replace the Q38 throttle body assembly.
Note: Disconnecting the throttle body harness connector may cause additional DTCs to set.
2. Ignition OFF, disconnect the harness connector at the Q38 throttle body assembly.
3. Ignition ON, verify that a test lamp does not illuminate between each motor control circuit listed below and ground.
* Motor control circuit terminal A
* Motor control circuit terminal B
瀚慖f test lamp illuminates, test the motor control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
4. Ignition ON, verify that a test lamp does not illuminate between each motor control circuit listed below and B+.
* Motor control circuit terminal A
* Motor control circuit terminal B
瀚慖f the test lamp illuminates, test the motor control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.
5. Ignition OFF, set the DMM to the 40 V scale, select the Min/Max Recording Mode, and set the Peak Min/Max response time to 1 ms.
Note:
* The DMM Min/Max Recording Mode and the response time of 1 ms must be reset after testing each circuit.
* The ignition must be OFF and the ECM completely powered down before testing each circuit.
6. Ignition OFF, measure the voltage using the DMM Min/Max Recording Mode function on each circuit listed below as the ignition is turned
ON. The Max voltage should be within 1 V of B+.
* Motor control circuit terminal A
* Motor control circuit terminal B
