Symptom Tree t005
| Cause | Correction |
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Air system leaks |
Block the vehicle wheels and check the air system for leaks with spring brakes applied and released. Check for leaks from the air compressor gaskets and the air system hoses, fittings, tanks, and valves. Refer to Procedure 012-019 and the OEM service manuals. Turn the keyswitch ON. Walk around the engine and listen for air leaks. |
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Air governor is malfunctioning or not set correctly |
Check the air governor for correct operation. Refer to the OEM service manual. |
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|
Air system component is malfunctioning |
Check the operation of check valves, alcohol evaporators, air dryers, and other OEM-installed air system components. Refer to the OEM service manual. |
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Carbon buildup is excessive in the air discharge line, downstream air valves, or cylinder head |
Check for carbon buildup. Replace the air compressor discharge line and cylinder head assembly if necessary. Refer to Procedure 012-003. Check the turbocharger for oil leaks. Check the intake tube for oil. Refer to Procedure 010-033. |
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Air dryer outlet check valve is sticking |
Lubricate or replace the air dryer outlet check valve assembly. Refer to the OEM service manual. |
