The importance of questioning the customer before the diagnostic process

Sept. 25, 2020
As I visit shops for the request of diagnostic support and a second set of eyes, there is typically a common trait among all of my mobile calls. There is almost always a missing piece of data. 

Does it ever cross your mind how some shops seem to struggle with complicated and many times hard-to-reproduce faults? Yet, others seem to “specialize” in such situations and remain profitable? No, it’s not magic or that the successful shops have more talented technicians, necessarily. It has to do with the ever-so-important “diagnostic game plan” that we mention so frequently here on the pages of Motor Age. And to be more specific, the interrogation process.

Turn up the heat

As I visit shops for the request of diagnostic support and a second set of eyes, there is typically a common trait among all of my mobile calls. There is almost always a missing piece of data. Sometimes this data simply cannot be obtained, like vehicles that don’t come with known service history (ie: vehicles acquired from an auto auction). But, more often than not, this critical data can be obtained quite easily. We just have to step up and ask for it.

The man who taught me everything I know about the diagnostic approach was the same guy who pounded this interrogation process into my brain. He ran a diagnostic/drivability shop in the Philadelphia area of Pennsylvania and (as the description denotes) specialized in deciphering hard-to-find drivability and electrical faults. His process was clear and repeatable, which made it easy to carry out.

The process began with a conversation that initiated before the vehicle even arrived. As the customer called the shop to arrange an appointment, the conversation led to the customer being allowed to drop the vehicle off ONLY if he/she could invest in a 20-minute conversation in the quiet atmosphere of the shop’s interrogation room. If the customer couldn’t invest that time, the appointment for analysis would be refused. The second and probably most important aspect of this customer interrogation process was a requirement for the complainant to be present for interrogation. What we sometimes fail to realize is that the person leaving the vehicle at the time of the appointment isn’t the one experiencing the “symptom.”

This reasoning may not seem obvious, but I distinctly recall a vehicle being dropped off for evaluation, with the complaint of brake failure. This occurred only hours after servicing of the evaporative emissions system (a leak between the induction system and the purge valve was repaired earlier that day). The concerned mother of the vehicle’s driver was irate as she experienced what she described as “brake failure.” The vehicle’s entire brake system was thoroughly inspected and extensive road-tests were carried out by multiple technicians. In the end, only after speaking directly with the “complainant,” it was discovered the vehicle’s brake system was performing as designed. I recall the statement from the concernedmother that the vehicle’s brake performance is “nothing like her high-end European sports car.” Thinking back, a well-conducted interrogation would’ve saved a lot of grief and embarrassment as well as time. The customer was simply comparing apples to oranges and was not comfortable with the brake performance of her daughter’s economy-class vehicle.

The point is, it’s the questions that don’t get asked that — many times — hold the key to the puzzle.

Understand that this diagnostic-specialty shop not only handled the “un-fixable” that the local area struggled with. It operated with only three technicians, a well-trained office staff (of two), and was handling, on average, 28 of these seemingly “impossible-to-solve” puzzles daily! To do that meant to have a game plan and that simply can’t occur (at the rate of 28-daily) without this “interrogation process,” to streamline the approach.

Beauty lies within the cup holder

Another situation existed when a thorough interrogation process could’ve saved a lot of time, headache, and in this case, a poor performance review. It was when a customer left the vehicle for routine service and upon retrieval, promptly returned the following morning for drop-off. It was accompanied by the complaint of “noise, anytime the vehicle is driven.” Of course, a thorough road test was conducted and the fault was not duplicable. The customer returned several times that week with the same complaint, but this time, much more frustrated. It was only on this final visit that a technician rode-along with the customer present. It was noted that the customer emptied the contents of her hip pocket, to the cupholder of the door panel, each time she entered. She retrieved the contents each time she exited. Included was a tube of lipstick and mascara. During the test drive, the annoying “rattle noise” the customer complained of was easily exhibited. It took no longer than 10 seconds to demonstrate the fault and prove to the customer the source of the noise. This was a lesson learned. No…she didn’t alter her review. Ouch!

The 8-hour road test

This final example was one from my archives. The subject vehicle was a 1988 Ford Thunderbird that was experiencing a very intermittent engine stall/restart with no other symptoms whatsoever. What made this lesson very hard learned is that I accepted this challenge and drove 85 miles (one-way) just to evaluate it!

As noted above, the fault was very intermittent. Due to the age of the vehicle, data was not very robust, so it was even more important to gain as much information that I could before I performed an evaluation. It was explained to me that the vehicle was not a regular customer of the shop I was assisting. It was a problem vehicle that had been through the ringer. The vehicle would stall on occasion for no apparent reason. I recall the vehicle stalling only once the entire day. Because of my long drive I was committed, so I stayed until I could reproduce that fault and hopefully capture it. Unfortunately, the fault didn’t occur for me that day. I had no choice but to abandon the challenge or return the following weekend — I chose the latter.

Upon my return, I chose instead to interrogate the customer. I asked the customer questions about the frequency of the stall. Questions about the weather and how long the car was running before the stall occurred came about. He mentioned that this didn’t occur until the engine was replaced a few months prior. I then inquired about rough roads, and his eyes lit up! He recalled the car stalling frequently on a particular road that was very bumpy. I performed a subsequent road test and quickly recreated the fault over a speed bump. I discovered that a connector, securing the wired harness to the ignition control unit was damaged and secured only with a zip-tie. I could wiggle the connector gently and the engine would stall each and every time!

Those experiences and stories (although hard to swallow) were career-changing for me. It’s these not-so-desirable experiences that allow us to grow as technicians. I hope to help you grow as well while avoiding the pitfalls and the wasted time I’ve encountered in my experiences growing up as a diagnostician. Developing a well-thought-out diagnostic game plan involves a logical thought process. But we can’t carry out our process with the blinders on. Always be aware of your surroundings and interrogate those customers. The difference between your success and another shop’s failure likely lies with what the customer knows but is not telling you!

About the Author

Brandon Steckler | Technical Editor | Motor Age

Brandon began his career in Northampton County Community College in Bethlehem, Pennsylvania, where he was a student of GM’s Automotive Service Educational program. In 2001, he graduated top of his class and earned the GM Leadership award for his efforts. He later began working as a technician at a Saturn dealership in Reading, Pennsylvania, where he quickly attained Master Technician status. He later transitioned to working with Hondas, where he aggressively worked to attain another Master Technician status.

Always having a passion for a full understanding of system/component functionality, he rapidly earned a reputation for deciphering strange failures at an efficient pace and became known as an information specialist among the staff and peers at the dealership. In search of new challenges, he transitioned away from the dealership and to the independent world, where he specialized in diagnostics and driveability. 

Today, he is an instructor with both Carquest Technical Institute and Worldpac Training Institute. Along with beta testing for Automotive Test Solutions, he develops curriculum/submits case studies for educational purposes. Through Steckler Automotive Technical Services, LLC., Brandon also provides telephone and live technical support, as well as private training, for technicians all across the world.

Brandon holds ASE certifications A1-A9 as well as C1 (Service Consultant). He is certified as an Advanced Level Specialist in L1 (Advanced Engine Performance), L2 (Advanced Diesel Engine Performance), L3 (Hybrid/EV Specialist), L4 (ADAS) and xEV-Level 2 (Technician electrical safety).

He contributes weekly to Facebook automotive chat groups, has authored several books and classes, and truly enjoys traveling across the globe to help other technicians attain a level of understanding that will serve them well throughout their careers.  

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