P1491: owner reports and bulletins

Powertrain (manufacturer-specific). We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got P1491 on your scanner? Tell the mechanic your year, make, model and any symptoms and you'll get the likely cause and what to check first. Ask about this code.

What owners report to NHTSA

6 complaints filed with NHTSA mention P1491, across 5 different models. The component owners most often filed it under: electrical system.

Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.