804081

What the code means

804081 stands for “Production readiness to drive: faulty” — a failure of the vehicle’s readiness-to-drive flag. In the case described, the code was logged on a BMW X5 (2019, G05) among a list of roughly 60 faults, most of which were tied to low electrical system voltage from an old or discharged battery. The same list included code 80402F (Battery deep discharged) and numerous “Undervoltage detected” entries.

That pattern is typical of a voltage sag: control modules register implausible states and log a cascade of faults unrelated to any real failure in specific systems. After the battery was replaced and registered, nearly all codes cleared and the vehicle ran normally with no warnings on the dash.

Symptoms

• The code shows up during diagnosis alongside many other low-voltage-related codes.
• The CEL was on; it went out after the fuel filler cap was tightened.
• No other symptoms are described in the source: according to the owner, the vehicle runs fine and the CEL is off.

Diagnosis and repair

1. Before clearing codes, check the freeze frame — timestamp and mileage. That tells you whether the codes appeared before or after the battery replacement: clearing wipes the freeze frame for good.
2. Check the battery’s condition and charge. In the case described, the battery had been replaced a month earlier and registered in the system the same week — after that, nearly all codes cleared.
3. Check that the fuel filler cap is tight: the CEL went out once it was tightened.
4. Clear all codes, drive for a day or two, then re-read faults.
5. Some codes don’t reset right away — the system needs to see a set number of engine starts or a set mileage. If everything works and there are no error messages on the display, you can ignore the codes that won’t clear and wait for them to reset on their own.