B3840 BMW Fault Code
Check B3840 OBD Fault Code ReasonBMW Mass Air Flow (MAF) Sensor Intermittent The MAF sensor circuit is monitored by the PCM for sudden voltage (or air flow) input change through the comprehensive component monitor (CCM).
If during the last 40 warm-up cycles in key ON engine running the PCM detects a voltage (or air flow) change beyond the minimum or maximum calibrated limit, a continuous memory diagnostic trouble code (DTC) is stored.
B3840 Code Symptoms :
The B3840 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. B3840 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 B3840
Parts or components should not be replaced with reference to only a B3840 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.
How to fix B3840 code ?
- Failures of clutch motion/travel sensors.
- Faulty oil control valve (OCV)
- Faulty select solenoid
- Fuel injectors may be faulty
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.