2010 Cadillac Truck SRX FWD V6-3.0L Page 1335
6. Test for 2.6-4.6 V between the control circuit terminal 2 and ground.
瀚慖f the voltage is not within the specified range, replace the K20 ECM.
7. If all circuits test normal, test or replace the Q42 turbocharger wastegate solenoid valve.
Component Testing
1. Ignition OFF, disconnect the harness connector at the Q42 turbocharger wastegate solenoid valve.
2. Test for 20-30 ohm between the control terminal 2 and the ignition terminal 1 of the Q42 turbocharger wastegate solenoid valve.
瀚慖f not within the specified range, replace the Q42 turbocharger wastegate solenoid valve.
3. Test for infinite resistance between each terminal and the Q42 turbocharger wastegate solenoid valve housing.
瀚慖f not the specified value, replace the Q42 turbocharger wastegate solenoid valve.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Turbocharger Disassemble ()
* Control Module References (See: Testing and Inspection/Programming and Relearning) for engine control module replacement, setup, and
programming
P0246
DTC P0244-P0246
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0244
- Turbocharger Wastegate Solenoid Valve Control Performance
DTC P0245
- Turbocharger Wastegate Solenoid Valve Control Circuit Low Voltage
DTC P0246
- Turbocharger Wastegate Solenoid Valve Control Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The engine control module (ECM) controls boost using the turbocharger wastegate solenoid valve. The wastegate valve is actuated by a rod from
the diaphragm box located at the housing. A spiral spring in the diaphragm box works in the closing direction while the pressure in the diaphragm
works in the opening direction. The ECM supplies a pulse width modulation (PWM) signal to a solenoid valve, which then allows pressure from
the turbo to come through. When the pressure overcomes the spring force in the diaphragm box, the rod begins to move, opening the wastegate
valve to a corresponding degree. The ECM changes wastegate valve opening by varying the PWM signal, which regulates the turbine speed.
