HOUSING 1T0085 - Caterpillar

System Operation Description:The balance valve actuator is used to control the actuation of the balance valves. The balance valves control the bypass of exhaust gas between the turbine wheels that are within the asymmetric turbocharger. Equalizing the pressure between the turbine wheels helps to reduce the possibility that the turbocharger will overspeed during engine operation.Use this procedure to troubleshoot the following codes:
Table 1
Diagnostic Trouble Codes
SPN Code and Description Conditions that Generate the Code System Response
5276-5 Engine Exhaust Manifold Bank 1 Flow Balance Valve Actuator Control Current Below Normal The Electronic Control Module (ECM) detects a low current in the circuit for the balance valve solenoid. The code is logged.
5276-6 Engine Exhaust Manifold Bank 1 Flow Balance Valve Actuator Control Current Above Normal The ECM detects a high current in the circuit for the balance valve solenoid.
5276-7 Engine Exhaust Manifold Bank #1 Flow Balance Valve Stuck Closed The ECM has determined that the operation of the balance valve actuator is suspect. The balance valve actuator and balance valve solenoid are integral components. The valve is designed with a normally open position. As the solenoid is energized, the valve is closed. Air flow to the diaphragms of the balance valves at the turbochargers is restricted. The valve vents residual air pressure that is in the air lines to the atmosphere.In order to test the balance valve actuator, a test apparatus that consists of the following tooling will be required:
Table 2
Required Tooling
Quantity Part Number
1 215-2592 Wastegate Kit
1 65120 7/16"-20 JIC to hose barb
1 93215 9/16"-20 JIC to hose barb
Illustration 1 g02140483
Schematic for the balance valve solenoid
Test Step 1. Check for Diagnostic Trouble Codes
Establish communication between Caterpillar Electronic Technician (ET) and the ECM. Refer to Troubleshooting, "Electronic Service Tools", if necessary.
Determine if a code is active or logged. Results:
No Active Codes - There are no codes active for the balance valve solenoid at this time, but operation of the balance valve actuator is suspect. Proceed to Test Step 2.
5276-7 Active - The ECM has determined that the operation of the balance valve actuator is suspect. Proceed to Test Step 2.
5276-5 Active - A 5276-5 is active or logged. There is a low current in the circuit for the balance valve solenoid. Proceed to Test Step 9.
5276-6 Active - A 5276-6 is active or logged. There is a high current in the