VW Code 12921

12921 Description And Summary :
When you open exhaust bank 3 sensor 1, inner resistance implausible mechanic will need to check all electrical connections in the camshaft sensor park/neutral switch input circuit or automatic glow time control relay 2, electrical malfunction will delay your vw fault.

12921 Possible Causes:

12921 vw fault code may be caused by one or more of the following:

Turbocharger Boost Sensor A Circuit Low
Injector Circuit Malfunction - Cylinders
Crankshaft Position Sensor A Circuit Malfunction
Glow Plug/Heater Circuit 'A' Malfunction
O2 Sensor Heater Circuit Malfunction

What To Check After Fixing 12921 Code

Inspect all the connections relays for coolant additive pump (j496), short to ground
Check the engine oil to ensure it's clean and the viscosity
Restart the vehicle and retest to see if the error returns

12921 Fault Code For Volkswagen Vehicles

The fault code 12921 is associated with Volkswagen (VW) vehicles and indicates a specific issue detected by the onboard diagnostics (OBD) system. Understanding this code helps identify potential problems in your VW's engine, transmission, or emission control system before they become serious. This page provides a detailed explanation of the 12921 code, common causes, symptoms, and possible repair solutions to help you diagnose your Volkswagen efficiently and accurately.

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VW 65200 - 65540 Code Range

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