87412A 3 Mercruiser TRIM CYLINDER ASS'Y, COMPLETE (STBD.)

Table 1
Diagnostic Trouble Codes
J1939 Code Description
(code descriptions may vary) Comments
2771-5 Engine Turbocharger Compressor Bypass Actuator #1 Control : Current Below Normal There is low current flow in the wiring between the Turbocharger Compressor Bypass Valve (TCBV) and the A5:E2 aftertreatment controller. Regenerations are disabled. The code is logged.
2771-6 Engine Turbocharger Compressor Bypass Actuator #1 Control : Current Above Normal There is excessive current flow in the wiring between the Turbocharger Compressor Bypass Valve (TCBV) and the A5:E2 aftertreatment controller. Regenerations are disabled. The code is logged.
2771-7 Engine Turbocharger Compressor Bypass Actuator #1 Control : Not Responding Properly The Turbocharger Compressor Bypass Valve (TCBV) is not responding properly to commands from the A5:E2 aftertreatment controller. The code is logged.
2771-3 Engine Turbocharger Compressor Bypass Actuator #1 Control : Voltage Above Normal There is excessive voltage on the signal wire between the Turbocharger Compressor Bypass Valve (TCBV) and the A5:E2 aftertreatment controller or there is an open circuit on the supply, signal, or return wire. The code is logged. Engine power is derated.
2771-4 Engine Turbocharger Compressor Bypass Actuator #1 Control : Voltage Below Normal There is low voltage on the signal wire between the Turbocharger Compressor Bypass Valve (TCBV) and the A5:E2 aftertreatment controller. The code is logged. Engine power is derated.
Follow the troubleshooting procedure in order to identify the root cause of the problem.
Illustration 1 g03761558
Table 2
Troubleshooting Test Steps Values Results
1. Determine the Diagnostic Code
A. Establish communication between Cat ET and the "Engine #1 Aftertreatment Controller". Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Record the logged codes or the active codes.
Diagnostic code
Result: A 2771-7 code is logged or active.
Proceed to Test Step 2.
Result: A 2771-3 or a 2771-4 code is logged or active. There is a problem with the wiring between the A5:E2 aftertreatment controller and the TCBV.
Proceed to Test Step 6.
Result: A 2771-6 code is logged or active. There is a problem with the wiring between the A5:E2 aftertreatment controller and the TCBV.
Proceed to Test Step 9.
Result: A 2771-5 code is logged or active. There is a problem with the wiring between the A5:E2 aftertreatment controller and the TCBV.
Proceed to Test Step 10.
2. Inspect the Wiring to the Turbocharger Compressor Bypass Valve (TCBV)
A. Inspect the wiring from the A5:E2 aftertreatment controller to the TCBV.
B. Check all connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect".
C. Check the wires for damage to the insulation.
D. Inspect the wires for the following conditions:
1. Exposed insulation
2. Rubbing of a wire against the engine
3. Rubbing of a wire against a sharp point
E. Perform a pull test on each wire terminal connection. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Damaged wire or connector
Result: A damaged wire or damaged connector was not found.
Proceed to Test Step 3.
Result: A damaged wire or damaged connector was found.
Repair the damaged wire or the damaged connector. Proceed to Test Step 3.
3. Perform the "Turbocharger Compressor Bypass Valve Test"
A. Perform the "Turbocharger Compressor Bypass Valve Test" in Cat ET.
Test completed successfully
Result: The "Turbocharger Compressor Bypass Valve Test" passed.
Proceed to Test Step 11
Result: The "Turbocharger Compressor Bypass Valve Test" failed.
Proceed to Test Step 4.
Illustration 2 g03765616
(1) Turbocharger Compressor Bypass Valve
(2) Engine Turbocharger
Table 3
Troubleshooting Test Steps Values Results
4. Inspect the Piping Between the Compressor and the TCBV
A. Inspect the tube between the compressor and the TCBV.
B. Check for cracks in the tubing.
C. Check for loose hardware or damaged hardware.
D. Check the clamps on the tube. Make sure that the clamps are tight.
Damaged tubing
Result: The tube is damaged or cracked.
Replace the tubing or repair the tubing. Proceed to Test Step 5.
Result: The tube is not damaged or cracked.
Replace the Turbocharger Compressor Bypass Valve.
Proceed to Test Step 5.
5. Perform the "Turbocharger Compressor Bypass Valve Test"
A. Perform the "Turbocharger Compressor Bypass Valve Test" in Cat ET.
Test completed successfully
Result: The "Turbocharger Compressor Bypass Valve Test" passed.
Proceed to Test Step 11.
Result: The "Turbocharger Compressor Bypass Valve Test" failed.
Replace the Turbocharger Compressor Bypass Valve. Verify the repair by repeating the "Turbocharger Compressor Bypass Valve Test in CAT ET". Proceed to Test Step 11.
6. Check the Voltage on the TCBV Circuit
A. Turn the keyswitch to the OFF position.
B. Verify that the harness connector is free of debris, free of corrosion and securely connected.
C. Disconnect the TCBV from the wiring harness.
D. Turn the keyswitch to the ON position.
E. Verify that there is +5 VDC between the SUPPLY (terminal 1) and RETURN (terminal 2) on the TCBV wiring harness connector.
F. Turn the keyswitch OFF.
+5 VDC
Result: There is 5 VDC between the SUPPLY and RETURN on the TCBV connector.
Proceed to Test Step 7.
Result: There is not 5 VDC between the SUPPLY and RETURN on the TCBV connector.
There is a problem with the wiring harness or the A5:E2 aftertreatment controller.
Make the necessary repairs. Replace parts, if necessary.
Proceed to Test Step 11.
7. Create an Open at the TCBV Connector
A. Turn the keyswitch OFF.
B. Disconnect the TCBV from the wiring harness.
C. Turn the keyswitch ON.
D. Monitor the diagnostic codes on Cat ET. Check for an active -3 diagnostic code for the TCBV.
E. Turn the keyswitch OFF.
Active -3 code
Result: A -3 diagnostic code became active after disconnecting the TCBV.
Proceed to Test Step 8.
Result: A -3 diagnostic code did not become active after disconnecting the TCBV.
There is a problem with the wiring harness or the A5:E2 aftertreatment controller.
Make the necessary repairs. Replace parts, if necessary.
Proceed to Test Step 11.
8. Create a Short at the Sensor Connector
A. Turn the keyswitch OFF.
B. Create a short between the SIGNAL (terminal 3) and RETURN (terminal 2) at the TCBV connector.
C. Turn the keyswitch ON.
D. Monitor the diagnostic codes on Cat ET. Check for an active -4 diagnostic code for the TCBV