P0048 - TURBOCHARGER BOOST CONTROL CIRCUIT HIGHFor a complete wiring diagram Refer to Section 8WWhen Monitored:With the ignition on and the Boost Pressure Servo Motor command on.Set Condition:The ECM detects that the (K137) Boost Pressure Servo Motor Control circuit is shorted to voltage for 0.5 second.
Possible CausesINTERMITTENT DTC(K137) BOOST PRESSURE SERVO MOTOR CONTROL CIRCUIT SHORTED TO VOLTAGE(K137) BOOST PRESSURE SERVO MOTOR CONTROL CIRCUIT OPEN OR HIGH RESISTANCEBOOST PRESSURE SERVO MOTORENGINE CONTROL MODULE (ECM)
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.(Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)Diagnostic Test1.DTC IS ACTIVEIgnition on, engine not running.With the scan tool, Clear DTCs in the Engine Control Module (ECM).With the scan tool, actuate the Boost Pressure Servo Motor at 100%.Monitor the scan tool for at least two minutes.With the scan tool, select View DTCs.Is the status Active for this DTC?YesGo To 2NoRefer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.(Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING)2.(K137) BOOST PRESSURE SERVO MOTOR CONTROL CIRCUIT SHORTED TO VOLTAGETurn the ignition off.Disconnect the Boost Pressure Servo Motor harness connector.Disconnect the Engine Control Module (ECM) harness connector.Remove the ASD Relay from the TIPM.Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay Connector.Turn the ignition on.Measure the voltage of the (K137) Boost Pressure Servo Motor Control circuit in the Boost Pressure Servo Motor harness connector.Is there any voltage present?YesRepair the (K137) Boost Pressure Servo Motor Control circuit for a short to voltage.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo to 33.(K137) BOOST PRESSURE SERVO MOTOR CONTROL OPEN OR HIGH RESISTANCETurn the ignition off.Remove the jumper wire and install the ASD RelayMeasure the resistance of the (K137) Boost Pressure Servo Motor Control circuit between the Boost Pressure Servo Motor harness connector and the Engine Control Module (ECM) harness connector.Is the resistance below 10.0 ohms?YesGo to 4NoRepair the (K137) Boost Pressure Servo Motor Control circuit for an open circuit or high resistance.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)4.BOOST PRESSURE SERVO MOTORTurn the ignition off.Connect the Engine Control Module (ECM) harness connector.Turn the ignition on.With the scan tool, actuate the Boost Pressure Servo Motor (Boost Pressure Actuator) to 100%.Using a 12 volt test light connected to 12 volts, check the (K137) Boost Pressure Servo Motor Control circuit in the Boost Pressure Servo Motor harness connector.The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.The circuit will remain actuated by the controller for 30 seconds. Be certain the actuation is active when checking the circuit.Is the test light illuminated and bright with the actuation at 100%?YesReplace the Boost Pressure Servo Motor in accordance with the Service Information.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo to 55.ENGINE CONTROL MODULE (ECM)Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Boost Pressure Servo Motor and the Engine Control Module (ECM).Look for any chafed, pierced, pinched, or partially broken wires.Look for broken, bent, pushed out or corroded terminals.Refer to any Technical Service Bulletins that may apply.Were any problems found?YesRepair as necessary.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoReplace the Engine Control Module (ECM) in accordance with the Service Information.Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)