U0797 Mercedes-benz 280 OBD Code

OBD/2 U0797 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 U0797 as an indication of a hard fault.

A good starting point in your diagnosis is checking all system fuses and fusible links. This can be done using the DVOM on the voltage setting. You will want to test the fuses with circuits loaded. Some fuses will appear normal until a load is placed on their respective circuit; at which point they will fail. This has been the cause of many 'phantom malfunctions'. Consult your vehicle information source for fuse and fusible link locations. If all fuses are in working order, you may want to check TCM relay operation by swapping identical relays. Usually the horn relay, starter relay, fuel pump relay, air conditioning clutch relay, and controller relays are similar enough in design to swap for diagnostic purposes.

U0797 Mercedes-benz 280 Error Code Repair Process :

The scent may U0797 signal oil or coolant leaking from their normally closed-loop systems, or it may indicate dangerous exhaust gases invading your car's interior. Car and truck exhaust contains toxic gases such U0797, so if the inside of your car injector high sides shorted together as if you were standing behind your car, get out and get it fixed. Fight the urge to take a little nap first. So sleepy. That's the carbon monoxide talking, friends. At least open a window on your way to the shop.

Common Causes of Mercedes-benz 280 U0797 OBD2 Code

A common cause of code U0797 is the failure of Injector High Sides Shorted Together, but there are several other possible causes as well, such as ;

Air fuel ratio (A/F) Sensor 1 Bank 1 circuit poor electrical connection
Engine Control Module (ECM)
Faulty Crankshaft Position Sensor (POS)
Damaged camshaft position (CMP) sensor

U0797 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.

U0797 Mercedes-benz 280 OBD Code

U0797 Mercedes-benz 280 Error Code Repair Process :

Common Causes of Mercedes-benz 280 U0797 OBD2 Code

U0797 code for other Mercedes-benz cars