U3963 Mercedes-benz S Class OBD Code

OBD/2 U3963 error code description and symptoms.

EGR Flow Insufficient Detected The EGR system is monitored during steady state driving conditions while the EGR is commanded on.
The test fails when the signal from the DPF EGR sensor indicates that EGR flow is less than the desired minimum. Vacuum supply EGR valve stuck closed EGR valve leaks vacuum EGR flow path restricted EGRVR circuit shorted to PWR VREF open to D.P.F. EGR sensor D.P.F. EGR sensor downstream hose off or plugged EGRVR circuit open to PCM VPWR open to EGRVR solenoid D.P.F. EGR sensor hoses both off D.P.F. EGR sensor hoses reversed Damaged EGR orifice tube Damaged EGRVR solenoid Damaged PCM Perform KOER self-test and look for DTC U3963 as an indication of a hard fault.

In most cases, the TCM is integrated into a single housing with the PCM. Nevertheless, the section of the module which controls (automatic) transmission function may be powered up separately. In any case, the TCM is typically powered using switched (only present with the ignition switch in the ON, start, or run position) voltage. This circuit is normally equipped with a fuse, fusible link, and/or a relay. Frequently, the PCM and TCM are powered using the same relay albeit by separate circuits. Access to a reliable vehicle information source will yield necessary details of the TCM power circuit for the specific vehicle in question.

U3963 Mercedes-benz S Class Error Code Repair Process :

For fuel temperature sensor #1 circuit short to ground check engine light 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. U3963 error code 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 fuel temperature sensor #1 circuit short to ground with your car's computers to find out exactly what's prompting the light to turn on.

Common Causes of Mercedes-benz S Class U3963 OBD2 Code

A common cause of code U3963 is the failure of Fuel Temperature Sensor #1 Circuit Short to Ground, but there are several other possible causes as well, such as ;

Air fuel ratio (A/F) Sensor 1 Bank 1 circuit poor electrical connection
Faulty front heated oxygen sensor
Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
Oil flow restriction in the oil passages or the variable camshaft timing (VCT) valve body

U3963 is a kind of Network Trouble Code

U-code indicates that engine communication errors and shows lost communication with engine parts.U-Codes are fairly straight forward, given all of the articles and technical publications that have been written regarding these problematic codes. In most cases, it just comes down to identifying the module that isn't communicating with the other modules on the CAN bus line for whatever reason.

U3963 Mercedes-benz S Class OBD Code

U3963 Mercedes-benz S Class Error Code Repair Process :

Common Causes of Mercedes-benz S Class U3963 OBD2 Code

U3963 code for other Mercedes-benz cars