Navigating the Challenges of Vehicle Repairs:

The Phantom Fix Syndrome in Truck Maintenance

Challenges of Vehicle Repairs, Truck Maintenance, Truck Repair, False Testing Results, Truck Technicians

The challenges of vehicle repairs during truck maintenance can be explained through the anecdote that many are familiar with – the old joke about the patient who complains, “It only hurts when I push here,” to which the doctor responds, “Don’t push there.” But what could the answer be if, when the doctor pushed in the same spot, the patient felt no pain? Or when truck technicians perform the same action to warrant the customer’s complaint, but no issue arose?

Perhaps the doctor’s touch provided a placebo effect or just worked some sort of unknown healing magic? Either way, the patient’s problem was resolved. That is unless the patient pushes the point again, the pain returns, at which point the patient returns to the doctor for another try.

The Challenges of Vehicle Repairs for Truck Technicians

Truck technicians may not be so fortunate during truck maintenance and repairs, as customers generally expect a single solution to a vehicle concern. Trying this or that until a complete repair transpires is not something shop customers are willing to accept or pay for. Nevertheless, anyone who has worked in the shop for very long will have experienced the dreaded phantom fix syndrome.

The Phantom Fix Syndrome Unveiled

This malady plays out thusly: the customer comes in with a vehicle complaint, and the truck technician cannot duplicate the concern; everything works as designed. The experience is aggravating for the customer who has experienced a problem, as well as for the technician who spends valuable time to no avail.

Sometimes it is extremely difficult to identify a problem when the problem evaporates during the investigation, especially with electronic testing. In some situations, the testing for the problem resolves the problem, at least temporarily. In other instances, the testing may cause the technician to believe all is well when, in truth, the testing procedure is creating a false result.

Common Causes of False Testing Results

There are multiple ways challenges of vehicle repairs arise, in which the truck technician may receive false testing results:

1. Poor Test-Lead Connection:

  • Probing with the test-lead may not be making good contact, resulting in an incorrect reading on the meter.
  • Back probing at a connector is often cautioned against in testing procedures because of the potential damage that could be done to the terminal, connector seals, and the connector. In addition, back probing makes it difficult to make a good connection with the circuit being tested.

2. Broken Circuit Misinterpretation:

  • When back probing a connector, the force, great or small, used to press the probe into the connector could push a broken circuit together, resulting in a good reading. However, as soon as the test pressure gets removed, the circuit breaks and the technician assumes the circuit passed the test.

3. Damage to Circuit Connection:

  • Probing at the connector can also cause a good circuit connection to fail. Pressing the terminals may spread them open to where they no longer make contact. Now, instead of tracing down the problem, the technician has created a second issue that may cause the same concern the customer complained about or a new concern. Unfortunately, if the damage results in the same concern, the technician may assume that the damaged connector was the primary cause of the customer’s original concern

4. Temporary Resolutions:

  • Simply disconnecting and reconnecting a connector can, at least temporarily, resolve a circuit terminal contact problem. Likewise, simply moving the harness around will often bring a poor connection to make contact.

Navigating the Path to Accurate Solutions

Each of the above situations has the potential to take a truck technician down a path that leads to false testing results. Not identifying a customer’s concern brings doubt to the shop’s ability to fix the customer’s vehicle accurately and quickly.

While every vehicle has some idiosyncrasies in how it operates that may need to be explained to the customer, each customer’s concern is real and should be investigated.

Will the technician always find the problem quickly? Of course not. Nevertheless, it will be time well spent for the technician to consult the service information for testing procedures on the vehicle to learn about any unique steps that need to be followed for solid testing.


Additional tips for repair and maintenance of Class 4-8 trucks may be found in the Mitchell 1 ShopConnection Truck blog.

EDITOR’S NOTE: Check out Jake Schell’s complete line-up of monthly columns in Fleet Equipment Magazine at

About the Author

Jake Schell

Jake Schell is an editorial consultant with Mitchell 1. Previously, he served as Product Manager for the Commercial Vehicle Group from 2002 to 2023. Prior to joining Mitchell 1, Jake spent 20 years as a technician. He holds a Chevrolet Master certification in the transmission category as well as ASE certifications in both cars and trucks.