Johnson: Read It or Weep: Automotive Maintenance Providers and Consumers Need Scan Tools - Part 1

A first-time customer drives into an automotive maintenance facility for an oil change; the service goes smoothly, and the customer is smiling. Six months and 5,000 miles later, the OEM dealer says the customer’s engine seized in highway traffic due to oil starvation, and they won’t cover it under warranty because the customer should’ve known not to exceed the “severe” service interval of 3,750 miles. The customer’s only option is to seek reimbursement from whoever serviced it last.  

The oil change service receipt shows the correct type and amount of engine oil was provided for the vehicle, as well as correct torque pressure on the oil drain plug, but service videos aren’t saved beyond three months and the customer is both skeptical and desperate. There’s 85,000 miles on the odometer, and it’s their only vehicle. 

The automotive maintenance facility’s manager tries to assist the customer for goodwill purposes even though the service warranty ended after 3,000 miles. When the manager inspects the car at the OEM dealership, however, there is no backsplash across the undercarriage consistent with a plug-out, the oil pan isn’t damaged, the drain plug is in place, and the oil filter looks intact and unclogged.  

The customer insists they saw no evidence of leakage prior to seizure, and any time a malfunction indicator light (MIL) went on from the time they bought the car, they always went straight to the OEM dealer who said everything was “normal.” That’s one of the reasons the customer followed the “normal” (i.e., longest) OEM-recommended oil change interval. 

Research into the year/make/model and engine type in an excessive oil consumption case like this one often reveals similar consumer complaints as well as Technical Service Bulletins regarding oil consumption testing and/or engine problems that tend to cause excessive oil consumption, such as incorrect rod bearing clearance.  

There may also be an engine-related warranty extension for the same engine but in a different model, which is the reason the customer wouldn’t have received any notification about it. Meanwhile, the owner’s manual recommendations for severe service intervals will, in hindsight, appear obvious now that the OEM dealer has highlighted those few pages of verbiage from the 500-page book. 

The customer’s means of transportation is on the line. 

The automotive maintenance facility’s reputation is on the line. 

The OEM dealer is offering to replace the engine for $10,000. 

Most insurance companies don’t go to the wall over claims that size. 

Are the customer and automotive maintenance facility just stuck holding the bag? 

This is where diagnostic trouble code (DTC) records come in. For better and worse, the phrase “laptop on wheels” accurately describes later model passenger vehicles. One of the biggest unforced errors consumers make is failure to protect their cars’ files. They’ll back up a $500 tablet but not their $50,000 transportation.  

Meanwhile, whatever “cloud” exists for passenger vehicle data is controlled by automakers, which is why giving data control to vehicle owners is an integral part of the Right to Repair campaign.  

However, that doesn’t mean consumers and aftermarket automotive service facilities are helpless unless Congress passes a new law. Good scan tools have the potential to catch engine malfunctions before disaster strikes as well as lessen the impact of OEM-related shenanigans especially regarding engine defects. 

A good onboard diagnostic (OBD II) scan tool can identify DTCs, turn off malfunction engine lights (MILs), erase certain DTCs, reset the OBD II system, and maintain records via app of a vehicle’s overall condition every time it’s used if an owner has two minutes to spare. The choice is no longer between $30,000 tools and tinker toys.  

I vetted Car and Driver’s list of top consumer scan tools and chose the Innova 5610 for its tech, customer service, OEM subscriptions, and reasonable price, as well as the company’s foresight in developing a free customer scan system with auto parts stores. OBD II knowledge is power.¹ 

This isn’t spin. Take it from the California Air Resources Board (CARB): 

“While all malfunctions that cause the light to illuminate either affect emissions or the ability of the OBD system to work properly, many also can affect fuel economy, and several can cause driveability problems or a decrease in overall performance. Manufacturers generally optimize their vehicles for performance, fuel economy, and emissions. As such, virtually any malfunctioning component can result in the vehicle running in a condition that is less than optimal.”² 

The DTC categories are Body, Chassis, Powertrain, and Network. Their corresponding codes start with their first letter. For the case described above, we’re interested in Powertrain DTCs, so those codes will start with a “P.” The generic or mandatory codes, i.e., the ones set by SAE that all automakers must include in their onboard systems per EPA and CARB regulations, have “0” as the second digit. If the second digit isn’t “0,” it’s an automaker-specific DTC. That will matter when it’s time to translate the information discovered. 

If a MIL is illuminated, a permanent DTC will be stored in the onboard system. However, the system also displays pending codes even if a malfunction hasn’t matured into triggering the MIL. That’s right—the onboard system has important functional data available to read with or without a lit MIL, but that pending data can be cleared by an OEM dealer or anyone else proficient with a good scan tool.  

That’s why maintaining a record of routine scans can be critical for consumers—it’s also why an automotive maintenance facility interested in challenging an OEM’s diagnosis would want to get over to the vehicle in question and scan it ASAP. 

To be continued: The second part of this column will be available online July 2024.  

^{1 Note: After researching scan tools and ultimately choosing the Innova 5610, the author received a complimentary unit from the manufacturer.}

^{2  https://ww2.arb.ca.gov/resources/fact-sheets/board-diagnostic-ii-obd-ii-systems-fact-sheet}