Check U3979 Engine Code

U3979 Engine

When you check engine light came on code U3979 the reason should be . However your vehicle's manufacturer may have a different definition for the U3979 OBD-II Diagnostic Network (U) Trouble Code. So you should chech it on our car models.

U3979 code can be about replacing a broken oxygen sensor can eventually lead to a busted catalytic convertor which can cost upwards of $2,000. Taking your car into a shop will cost you around $200 depending on the car. However, an oxygen sensor is easy to replace on many cars and is usually detailed in the owner's manual. If you know where the sensor is, you only have to unclip the old sensor and replace it with a new one. Regardless of how you approach it, you should get this fixed right away.

U3979 Possible Solution:

Power Steering Pressure (PSP) Switch Signal Malfunction The PCM counts the number of times vehicle speed transitions from 0 to a calibratable speed. After a calibratable number of speed transitions the PCM expects that the PSP input should have changed. This DTC is set if the transition is not detected. Vehicle towed with engine running Power steering hydraulic concern was repaired but DTC was not erased PSP switch/shorting bar damaged SIG RTN circuit open PSP circuit open or shorted to SIGRTN PCM damaged Check, if possible, if vehicle was towed or power steering service was performed. Observe PSP V PID while checking wires for intermittents.

U3979 Code Meaning :

U 3 9 7 9
OBD-II Diagnostic Network (U) Trouble Code For Engine Ignition System Or Misfire Injector Circuit Malfunction - Cylinders Cylinder 10 Contribution/balance Fault Reverse Input Circuit

Regarding the U3979 code, it would probably be worthwhile to carefully inspect the wire harness near the intake manifold bracket. This is done most easily from below the car in the area near the oil filter.

U3979 OBD-II Diagnostic Network (U) Trouble Code Description

U3979 engine trouble code is about Reverse Input Circuit.

Reason For U3979 Code

The reason of U3979 OBD-II Engine Trouble Code is Injector Circuit Malfunction - Cylinders.

Parts or components should not be replaced with reference to only a U3979 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.