5036610 JOHNSON HOLDER, ENGINE

Illustration 1 g06203138
Schematic for the circuit of the actuator for the bypass valve
Test Step 1. Inspect the Electrical Connectors and Wiring
Remove the electrical power from the engine.Note: For the following steps, refer to Troubleshooting, "Electrical Connectors - Inspect".
Thoroughly inspect each of the following connectors:
J1/P1 connectors
J9/P9 connectors
Connectors on the actuator for the bypass valve
Check the torque of the allen head screw for the ECM connectors.
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the actuator for the bypass valve.
Illustration 2 g00935459
Right side views
Check the wiring for abrasion and for pinch points from the actuator for the bypass valve to the ECM.Expected Result:All of the connectors, pins, and sockets are connected properly. The connectors and the wiring do not have corrosion, abrasion, or pinch points.Results:
OK - The components are in good condition with proper connections. Proceed to Test Step 2.
Not OK - The components are not in good condition and/or at least one connection is improper.Repair: Perform the necessary repairs and/or replace parts, if necessary. Ensure that all the seals are properly installed. Ensure that the connectors are properly engaged. Verify that the repair has eliminated the original problem.STOPTest Step 2. Check for a Diagnostic Code
Connect the Caterpillar Electronic Technician (ET) to the service tool connector.
Switch the 35 amp circuit breaker ON. Set the engine control to the STOP mode.
Use Cat ET to determine if one of the following diagnostic codes is active:
1720-9 Turbocharger Compressor Bypass Valve Actuator : Abnormal Update Rate
1720-11 Turbocharger Compressor Bypass Valve Actuator invalid
1720-12 Turbocharger Compressor Bypass Valve Actuator : FailureExpected Result:None of the diagnostic codes are active.Results:
OK - None of the diagnostic codes are active. The communication between the ECM and the actuator for the bypass valve appears to be OK at this time. However, diagnostic codes may be logged.Repair: If you are troubleshooting an intermittent problem, refer to Troubleshooting, "Electrical Connectors - Inspect".Terminating resistors must be connected to each end of the CAN data link. The terminating resistors improve the communication between the devices. If there is an intermittent diagnostic code for any of the devices that are connected to the CAN data link, be sure to check the terminating resistor that is inside the terminal box. Also check the jumper wire that is connected between terminals "J" and "K" on the actuator for the bypass valve. Make repairs, when possible. Replace parts, if necessary.STOP
Not OK (Active 1720-9) - The ECM has detected a problem with the communication between the ECM and the actuator for the bypass valve. Proceed to Test Step 3.
Not OK (Active 1720-11) - There is an active 1720-11 diagnostic code. This code indicates a problem with the movement of the actuator for the compressor bypass.Repair: The actuator for the compressor bypass valve must be installed properly to provide stable operation. If the motion is sticky and/or rough, investigate the cause of the binding. Perform the necessary repairs.STOP
Not OK (Active 1720-12) - There is an active 1720-12 diagnostic code.Repair: The actuator for the bypass valve has detected an internal fault. Replace the actuator. Verify that the repair has eliminated the original problem.STOPTest Step 3. Check for Electrical Power at the Actuator
Illustration 3 g01234707
Locations for the voltage check at the junction box
Refer to Illustration 3. Measure the voltage at the junction box.
Disconnect the electrical connector from the actuator.
Illustration 4 g01233703
Locations for the voltage check at the harness connector
Measure the voltage between terminals "N" and "P" at the harness connector.Expected Result: