40136 8 Mercruiser NUT, (M8) Stainless Steel

Table 1
Diagnostic Codes Table    
Description    Conditions which Generate this Code    System Response    
526-5 Turbo Wastegate Drive current below normal     The Electronic Control Module (ECM) detects current that is below normal.     The code is logged.
If equipped, the warning light will illuminate.
The engine will be derated.    
526-6 Turbo Wastegate Drive current above normal     The ECM detects current that is above normal.    
526-7 Turbo Wastegate Drive not responding properly     The ECM detects current that is below normal.     The code is logged.
If equipped, the warning light will illuminate.
The engine has low power and the engine may not reach top RPM.
The engine produces excessive black smoke.    The engine utilizes a turbocharger with an electronically controlled wastegate. The wastegate is a mechanical valve that is used to regulate the intake manifold (boost) pressure.The required intake manifold (boost) pressure is calculated by the software that is contained in the ECM. The wastegate solenoid is controlled by a signal from the ECM.
Illustration 1 g02710265
Schematic for the wastegate regulator
Illustration 2 g01228040
Connector for the wastegate solenoid (1) Return (2) Signal
Illustration 3 g01332545
Typical view of the pin locations on the P2 connector (17) Wastegate signal (19) Wastegate return
Illustration 4 g01172794
Wastegate regulator (1) Wastegate regulatorTest Step 1. Inspect Electrical Connectors and Wiring
Remove the electrical power from the ECM.
Thoroughly inspect the terminal connections on the P2/J2 ECM connectors. Thoroughly inspect any connectors that may be associated with the wastegate.
Refer to service Troubleshooting, "Electrical Connectors - Inspect".
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the wastegate.
Check the torque of the allen head screws for the ECM connectors. Refer to service Troubleshooting, "Electrical Connectors - Inspect".
Check the harness for abrasions and for pinch points from the wastegate back to the ECM.
If applicable, use Caterpillar Electronic Technician (ET) to perform a "Wiggle Test".Expected Result:All connectors, pins, and sockets are correctly coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The harness and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem in the wiring and/or the connectors.Repair: Repair the connectors or the harness and/or replace the connectors or the harness. Ensure that all of the seals are correctly in place and ensure that the connectors are correctly coupled.Use Cat ET in order to clear all logged diagnostic codes and then verify that the repair eliminates the problem.STOPTest Step 2. Check for Diagnostic Codes
Restore the electrical power to the ECM. Access the "Diagnostics Tests" on Cat ET. Activate the "Turbo Wastegate Solenoid Test". Wait at least 30 seconds in order for the result to be displayed.Expected Result:Cat ET displays no diagnostic codes.Results:
OK - There are no active codes.Repair: The original codes may have been caused by a loose connector. If this situation is an intermittent problem, refer to service Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - Diagnostic code 526-5 is active at this time. Proceed to Test Step 3.
Not OK - Diagnostic code 526-6 is active at this time. Proceed to Test Step 5.Test Step 3. Create a Short Circuit in the Harness at the Solenoid
Remove the electrical power from the ECM.
Disconnect the connector for the wastegate solenoid.
Install a jumper wire between Terminal 1 and Terminal 2 on the connector for the wastegate solenoid.
Restore the electrical power to the ECM. Activate the "Turbo Wastegate Solenoid Test" on Cat ET. Wait at least 30 seconds in order for the result to be displayed.
Check for active diagnostic codes on Cat ET.
Remove the electrical power from the ECM and return all wiring to the original configuration.Expected Result:Diagnostic code -6 is now active.Results:
OK - Diagnostic code -6 is now active. There is a problem with the solenoid.Repair: Perform the following procedure:
Temporarily connect a replacement wastegate regulator.
Restore the electrical power to the ECM. Use Cat ET in order to clear all logged diagnostic codes and then activate the "Turbo Wastegate Solenoid Test" on Cat ET. Wait at least 30 seconds in order for the result to be displayed.
Diagnostic code -5 is no longer active.
If the -5 code is resolved, reconnect the suspect wastegate regulator. If the problem returns, permanently install the replacement wastegate regulator.
Use Cat ET in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.STOP
Not OK - The -6 diagnostic code (open circuit) is still active. Proceed to Test Step 4.Test Step 4. Create a Short Circuit at the ECM
Remove the electrical power from the ECM.
Disconnect the P2/J2 ECM connector and remove the wires from P2-17 and P2-19.
Install a jumper wire between P2-17 and P2-19 in order to create a short circuit.Note: Reconnect the P2/J2 ECM connector.
Restore the electrical power to the ECM. Activate the "Turbo Wastegate Solenoid Output" on Cat ET. Wait at least 30 seconds for activation of the diagnostic codes.
Check for active diagnostic codes on Cat ET.Expected Result:Diagnostic code -6 is now active.Results:
OK - Diagnostic code -6 is now active. There is a problem in the harness between the ECM and the solenoid.Repair: Repair the harness or replace the harness.Use Cat ET in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.STOP
Not OK - The -5 diagnostic code is active.Repair: Perform the following procedure:
Connect a test ECM. Refer to service Troubleshooting, "ECM - Replace" and refer to service Troubleshooting, "Test ECM Mode".
If the test ECM resolves the problem, reconnect the suspect ECM. If the problem returns, permanently install the new ECM.Use Cat ET in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.STOPTest Step 5. Disconnect the Solenoid in order to Create an Open Circuit