3 Tips for Fast Effective Fault Isolation

Here are some basic rules you should always follow to ensure successful troubleshooting when you’re dealing with an engine issue such as high ITT or low oil pressure.

1. CONSULT THE MANUAL FIRST
Whenever the Pratt & Whitney support team at the Customer First Centre (CFirst) receives a phone call or email from an operator about fault isolation, they begin by consulting Section 72.00.00 of the engine maintenance manual (EMM) and following the procedure outlined there.

That’s what customers should do too, explains Julien Arsenault-Hurtubise, Technical Specialist, CFirst. “The fault isolation section of the engine maintenance manual is your best friend,” he says. “If there’s low oil pressure, the first thing you should do is open up the manual and see if there’s a fault isolation for it. Most of the time, you’ll find the issue this way,” he notes.

“All of Pratt & Whitney’s knowledge of our engines is built into the fault isolation chart. It’s very effective for rapidly and accurately identifying the issue. It’s our number-one tool for helping customers troubleshoot. We never deviate from it.” – Julien Arsenault-Hurtubise, Technical Specialist, CFirst

To speed up the troubleshooting process, Julien recommends that customers perform the steps in the fault isolation section before contacting CFirst.

2. DON’T SKIP ANY STEPS
Experienced operators may intuitively know many of the steps to be taken. However, Julien urges customers to not perform troubleshooting without referring to the manual.

If, for example, the engine doesn’t start, there are various elements that need to be checked. “Using fault isolation will give you a detailed answer, not just the big picture. It will help you get the whole story prior to contacting CFirst,” he remarks.

Some newer engines, including the PW800 family and PT6E series no longer have a fault isolation section in the EMM. Instead, they use a software tool called SpotLight^®. This essentially replicates the fault isolation procedure in the manual based on information input by the customer, leading to a probable cause and recommended action.

“CFirst is available 24/7 to give you support and guidance when you need it. We also encourage customers to be proactive and save time in the troubleshooting process by taking it from the top and making sure they go through all the steps in the EMM in order.” – Julien Arsenault-Hurtubise, Technical Specialist, CFirst

3. KEEP TRACK OF EVERYTHING YOU DO
“In addition to following the steps in the fault isolation process, we need to know the actual observed results,” notes Julien.

If the fault isolation procedure calls for checking the resistance, for instance, take a note of the number so you can share it with CFirst. If they have the detailed results, the CFirst support team can factor this into their analysis of the situation.

It's also possible that a fault isolation process will carry over between shifts and be handled by two different mechanics. Keeping track of everything is therefore important so the second mechanic will know what has been done already and what the results were.

Finally, Julien notes that whenever you do checks as part of a fault isolation, and P&WC has been involved, even if you resolve the issue on your own, it’s a good idea to share the results with CFirst, who will document them for future reference, as well as learning and product improvement.

For more on how sharing information helps the CFirst team provide you with better support, check out our article Why Pilot Reports Are Vital for Engine Issue Resolution.