MANIFOLD 9W8439 - Caterpillar

Know the Machine
Understand the operation of the machine. Know if the symptom is a characteristic of normal operation or if the symptom is a failure.Read the systems operation information in order to understand the systems of the machine. Understand the interaction of the machine systems.Understand the Symptom
Speak with the operator about the symptom. Acquire the following Information:
The performance of the machine prior to the failure
First occurrence of the symptom
The operating conditions at the time of the failure
The sequence of events prior to the failure (order of the occurrences)
The troubleshooting steps that have been taken
The history of repairs of the machine
The preventive maintenance of the machine
Related service information about current problems that affect the serial number of the machine
Inspect the Machine. Look for problems. Notice any unusual odors in the air. Listen for unusual noises.Perform the "Visual Inspection" steps. Refer to Troubleshooting, "Machine Preparation for Troubleshooting".Verify the Symptom
When possible, attempt to duplicate the symptom. Operate the machine and repeat the conditions that caused the failure. Check the gauges inside the cab. Notice any unusual odors in the air. Listen for unusual noises.Determine if the ECM has detected any faults. A diagnostic code is used to specify each detected fault.Determine Possible Causes
Use the information from the operator and your inspection. Attempt to identify a common cause if there is more than one symptom.If you troubleshoot diagnostic codes and the problem is not resolved, continue troubleshooting using the "Symptom Troubleshooting" section of this manual. Identify the component that is the most probable cause of the symptom.Test and Repair the System
Use the tests and procedures in this manual to verify the cause of the symptom. Once the cause has been identified, repair the failure. Then, test the system again in order to verify that the symptom is resolved.Provide Feedback to Caterpillar
Share your troubleshooting information. After the repair has been performed: Use the form in "SIS", or in "CBT" feedback to write a brief description about the symptom, testing, and repair of the machine. Include your phone number or your e-mail address so that you can be contacted. This feedback information helps Caterpillar improve service information.