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B1794 BMW Fault Code

Check B1794 OBD Fault Code Reason
Description:

Catalytic converters must be warm before they can work properly. On a cold start the PCM provides a rich mixture to keep the cold engine running.
All that extra fuel goes into the catalytic converter. But the exhaust isn't very hot, because, ah, the engine is pretty cold. GM has employed several strategies to fire up the catalytic converter quicker and reduce cold start emissions. One way is to use a secondary air pump that pumps outside air directly into the catalytic converter.

B1794 Code Symptoms :

See B1794 in engine

The B1794 Check Engine lamp is perhaps the most troubling of lights because it could mean so many different things, from you didn't screw the gas cap on tightly enough to look out for pistons flying through the hood and into the stratosphere. The easiest way to find out what this light is telling you is to hook your vehicle up to a scan tool. B1794 diagnostic tool looks a little like an oversized calculator and plugs into a communication port inside the car. After you instruct it to perform the scan, it speaks with your car's computers to find out exactly what's prompting the light to turn on.

Diagnosis And Repairing B1794

Parts or components should not be replaced with reference to only a B1794 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.

How to fix B1794 code ?

  • Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
  • Faulty Intake Valve Timing Control Solenoid Valve
  • Faulty Crankshaft Position Sensor (POS)
  • Faulty starter motor

On some transmissions, such as automated manual transmissions or automatic transmissions with manual mode, the GSP switch lets the TCM know whether or not the driver has selected automatic or manual function.

On manual transmissions, the GSP switch informs the TCM which gear the driver is selecting, and may function as a neutral safety switch, depending on system design. The TCM also uses the gate select position switch to monitor transmission operation. For example, if the driver selects manual mode and selects 3rd gear on an automatic transmission, the TCM may monitor speed sensors to detect clutch and brake slippage.

BMW Cars that meet B1794 error