B204D Audi Variant OBD Code

OBD/2 B204D error code description and symptoms.

The Transmission Fluid Pressure Switch allows the engine's control module (PCM) or Transmission Control Module (TCM) to use hydraulic fluid to engage the clutches in the transmission to allow for smoother shifting while driving. If the PCM or TCM detects an issue with the hydraulic clutch or the pressure switch, the PCM or TCM will set code B204D

As long as the throttle plate remains closed, the idling speed and quality is controlled by the PCM via the idle control valve, and as can be seen from the above it should be clear that idle control on a gasoline engine is a complex affair. For instance, if the engine is started in sub-zero temperatures, the PCM will command the idling control valve to allow less air to enter the engine to enrich the air/fuel mixture to create a condition which is roughly analogous to how chokes worked on carburetted engines to control idling in cold weather.

B204D Audi Variant Error Code Repair Process :

If your vehicle failed a B204D test and the B204D Check Engine Light is NOT on, chances are you have a problem with the OBDII system, a burned out MIL lamp, or a faulty catalytic converter. The converter is essentially an afterburner that cleans up the exhaust after it exits the engine. The OBDII system uses aux heater glow plug circuit short to ground a ownstream oxygen sensor to monitor the efficiency of the converter, and it should detect a drop in converter efficiency if the converter has been contaminated or is failing (ignition misfiring, leaky exhaust valves, and oil burning can all damage the converter). What you want to look aux heater glow plug circuit short to ground: Any conditions that might cause ignition misfire, an overly rich or lean fuel condition, or loss of compression. Use your OBD Express DIY to look at the oxygen sensor outputs, coolant temperature, airflow, calculated engine load, and inlet air temperature.

Common Causes of Audi Variant B204D OBD2 Code

A common cause of code B204D is the failure of Aux Heater Glow Plug Circuit Short to Ground, but there are several other possible causes as well, such as ;

Continuous oil flow to the VCT piston chamber
Faulty Crankshaft Position Sensor (POS)
Intake Valve Timing Control Solenoid Valve harness is open or shorted
Fuel filler cap remains open or fails to close

B204D is a kind of Body Trouble Code

Auto body problems aren't always easy to spot. Diagnosing auto body problems sometimes requires a little know-how. In this section you'll find articles dedicated to teaching you how to diagnose auto body problems.

Engine OBD 2 Codes website is a freeware resource center for engine trouble codes.

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B204D Audi Variant OBD Code

B204D Audi Variant Error Code Repair Process :

Common Causes of Audi Variant B204D OBD2 Code

B204D code for other Audi cars