C0389 Trouble Code

View C0389 obd/2 error code description and symptoms. C0389 engine photo

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 C0389 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.

C0389 Error Code Repair Process :

OBD C0389 code and tailpipe testing are two different approaches to identify vehicles in need of repair. The OBD system looks for broken or malfunctioning emissions control components and seatbelt passenger pretensioner circuit short to ground, while tailpipe tests sample a vehicle's exhaust to see if it is above or below certain prescribed limits. Given the robust nature of today's emissions control components, it is entirely possible for an individual component to C0389 malfunction without leading to an immediate increase in emissions at the tailpipe. In such cases, other components (like the catalyst) can temporarily compensate for the part that is broken however, these other components can only do double duty for so long before they, too, begin to malfunction. In addition, OBD also monitors for C0389 and other malfunctions in the fuel system problems that traditional tailpipe tests were not designed to identify. Most state and local areas also include a gas cap pressure test as part of an emission inspection.

C0389 is a kind of Chassis Trouble Code

Diagnosing chassis noises can be one of the most frustrating problems technicians face. Fortunately, manufacturers have engineered noise, vibration and harshness (NVH) diagnostic techniques and equipment to find the source of the noise.

Common Causes of C0389

A common cause of code C0389 is the failure of Seatbelt Passenger Pretensioner 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
Exhaust tube
EVAP canister or fuel tank leaks
Dirty Oil

C0389 Trouble Code

C0389 Error Code Repair Process :

Common Causes of C0389

C0389 code for all cars