Engine Diesel Engines
• The position of the EGR valve is controlled by the PCM, which activates the DC motor
via a duty signal.
M6FL_01080
1 DC motor 3 Current detection circuit
2 PCM
• At low engine speeds the PCM controls the DC motor with a large duty cycle, so that the
EGR valve opens and exhaust gas is recirculated.
• At high engine speeds the PCM controls the DC motor with a small duty cycle, so that
the EGR valve closes and no exhaust gas is recirculated.
• In order to remove any carbon deposits from the EGR valve seat a cleaning mode is
activated each time the engine is shut off. Therefore, the PCM actuates the EGR valve
so that it is moved from the fully open to the fully closed position several times. This
process takes approx. 10 s.
• The PCM controls the DC motor by a duty signal 0 V/12 V.
NOTE: If the EGR system fails, the EGR valve stays in the closed position in which no
exhaust gas is recirculated.
Service Training Mazda6 Facelift 01-53
To Next Page
