Man trusted the dealership to fix his car — twice. Now they want $1,600 more, and he’s questioning everything

A 2017 Nissan Maxima owner is frustrated after taking his car to the dealership twice for power loss issues, only to now be quoted over $1,600 for what he believes may have been the root cause all along. TikTok user @desertmountainbiker shared his story, describing a series of escalating repair bills and “shady vibes” from the service center.

In his TikTok video, he said the problems started when his Maxima went into limp mode, which is when a car intentionally limits its power to protect key components. The dealership’s diagnostic pointed to a transmission issue, and they recommended replacing the valve body at a “reduced cost.”

That fix didn’t last. According to Motor1.com, just four weeks later, the car was back in limp mode and wouldn’t even start, forcing him to have it towed back to the dealership. This time, Nissan corporation stepped in with a “good-faith estimate” and agreed to cover half the cost of a full transmission replacement.

The dealership’s shifting diagnoses are raising real questions about how thorough the original inspection was

After the transmission was replaced, the dealership called with a brand new diagnosis: a failed diode on the alternator had caused the battery to swell from overvoltage. Notably, there were no dashboard warning lights or any signs of electrical problems during the four weeks between the first and second repairs. The dealership is now quoting him over $1,600 to replace the alternator, battery, and wiring harness.

He suspects these electrical problems could have been the root cause of the original limp mode and the transmission fault codes from the very beginning. It’s a reasonable concern, since a comprehensive diagnostic would typically be expected to catch a failing alternator or a swelling battery. 

Dealership visits don’t always go smoothly, as one woman discovered when she paid $25 for a mystery car rental and ended up with a surprising result. Experts note that limp mode can be triggered by many things beyond transmission problems, including a weak or dead battery, faulty sensors, loose wiring connections, or air hose leaks. So the idea that an electrical fault caused the original issue is not far-fetched.

Other 2017 Nissan Maxima owners on car forums have reported similar “phantom battery drain” problems that were difficult to diagnose. Some experienced their cars failing to start, just like he did, and many suspected a bad wiring harness or an electrical short as the cause. Car owners are also being reminded to watch out for hidden dangers under the hood, as a Toyota mechanic recently warned about a surprising risk that many people overlook.

It’s also worth noting that the 2017 Nissan Maxima was subject to a recall affecting over 700,000 vehicles for a brake fluid leak that could cause an electrical short and raise the risk of fire. While not directly tied to his situation, it does show that electrical vulnerabilities existed in that model year. Having already paid for two major repairs, he now faces another large bill for what may have been the underlying problem from the start.