TURBO GP-BASIC 2472967 - Caterpillar

The following background information is related to this procedure:Electronically Controlled WastegateThe C7.1 engine has a turbocharger with an electronically controlled wastegate. Typically, the wastegate is a mechanical valve that is used in the turbocharger in order to regulate the intake manifold pressure to a set value.The control system for the electronically controlled wastegate precisely regulates the intake manifold pressure by using a wastegate regulator to control the wastegate.The required intake manifold pressure is calculated by the software that is contained in the ECM. The ECM uses the wastegate regulator to control the wastegate in order to provide the precise value of intake manifold pressure. The solenoid in the wastegate regulator is controlled by a PWM signal from the ECM.Suction Control Valve for the High-Pressure Fuel PumpThe fuel rail pump solenoid is used to control the output from the fuel rail pump. The solenoid receives an electrical supply from the ECM. The fuel rail pump solenoid is then energized when the fuel is to be pumped into the fuel rail.The amount of fuel that is required is calculated by the software that is contained in the ECM. The fuel pump solenoid is controlled by a PWM signal from the ECM.
Illustration 1 g03377232
Schematic for the solenoid valves
Illustration 2 g03377258
Pin locations on the P2 connector for the solenoid valves
(25) Wastegate regulator PWM signal (C7.1 engine only)
(26) Wastegate regulator return (C7.1 engine only)
(17) High pressure fuel pump solenoid PWM signal
(19) High pressure fuel pump solenoid return
Table 2
Troubleshooting Test Steps Values Results
1. Inspect Electrical Connectors and Wiring
A. Thoroughly inspect the terminal connections on the P2/J2 ECM connector and the solenoids.
Refer to Troubleshooting, "Electrical Connectors - Inspect".
B. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector and the solenoid connectors that are associated with the active diagnostic code.
C. Check the screw for the ECM connector for the correct torque of 5 N m (44 lb in).
D. Check the harness for corrosion, abrasion, and pinch points from the solenoids to the ECM.
Loose connection or damaged wire
Result: There is a fault in a connector or the wiring.
Repair: Repair any faulty connectors or replace the wiring harness. Ensure that all of the seals are properly in place and ensure that the connectors are correctly coupled.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.
Result: All connectors, pins, and sockets are correctly coupled and/or inserted. The harness is free of corrosion, abrasion, and pinch points.
Proceed to Test Step 2.
2. Check for Active Diagnostic Codes
A. Turn the keyswitch to the OFF position.
B. Connect the electronic service tool to the diagnostic connector.
C. Turn the keyswitch to the ON position. Wait at least 20 seconds for activation of the diagnostic codes.
D. Verify if any of the diagnostic codes that are listed in Table 1 are active.
E. Turn the keyswitch to the OFF position.
Diagnostic codes
Result: A 1076-5 18-5 or 1188-5 526-5 diagnostic code is