P26AB: owner reports and bulletins

Powertrain (generic, all makes). We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got P26AB 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

5 complaints filed with NHTSA mention P26AB, 5 of them since 2015, across 1 different models. The component owners most often filed it under: electrical system.

Most-reported models

VehicleComplaintsModel years reported
RAM 150052014, 2015, 2016

Manufacturer service bulletins that name P26AB

15 technical service bulletins and manufacturer communications filed with NHTSA mention P26AB, from 1 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • RAM 1500 (2015), bulletin 10191425: 5.7L P26AB Engine coolant bypass valve stuck.

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.