U1678 BMW Fault Code

Description:

Vehicle Speed Sensor (VSS) Intermittent Indicates the powertrain control module (PCM) detected an error in the vehicle speed information. Vehicle speed data is received from either the vehicle speed sensor (VSS), transfer case speed sensor (TCSS), anti-lock brake system (ABS) control module, generic electronic module (GEM), or central timer module (CTM). This DTC is set the same way as U1678. However, it is intended to flash the transmission control indicator lamp (TCIL) for first time VSS circuit error/malfunctions. Refer to possible causes for U1678

U1678 Code Symptoms :

The rule of U1678 code when it comes to emissions-related vehicle repair is that any modification that changes the vehicle from a certified configuration to a non-certified configuration is considered tampering: this applies to both vehicle owners and repair facilities and is, therefore, a Federal offense. Replacing a catalyst with a straight pipe is one traditional example of U1678.

Likewise, overriding the OBD system through the use of high-tech defeat devices or non-certified computer chips, for example, would also be considered tampering. The OBD system may, however, be repaired back to its original certified configuration with certified performance chips or appropriate aftermarket parts.

Diagnosis And Repairing U1678

Parts or components should not be replaced with reference to only a U1678 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.

How to fix U1678 code ?

• Clogged or faulty fuel injector (s)
• Faulty Crankshaft Position Sensor (POS)
• Faulty Fuel injector
• Faulty Air Flow Meter