B279A – Deterrent System Communication

B279A Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

B279A Possible Causes

Faulty Key,Faulty Transponder Key Electronic Control Unit (ECU),Transponder Key Electronic Control Unit harness is open or shorted,Transponder Key Electronic Control Unit circuit poor electrical connection,Faulty Engine Control Module (ECM)

B279A Description

If the communication line to the Transponder Key Electronic Control Unit (ECU) assembly is stuck on HI output, the Engine Control Module (ECM) sets the OBDII code.