Mazda CX-5 Service & Repair Manual: Air Fuel Ratio (A/F) Sensor Heater Control
Outline
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Based on the control of the A/F sensor heater, a stabilized oxygen concentration is detected even at low exhaust temperatures, and feedback control of fuel injection even at cold engine start is made possible for improved cold temperature exhaust emission performance.
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Both emission performance and sensor protection have been improved by duty control of the heater according to engine operation conditions (exhaust gas temperature).
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A pre-heater has been adopted to prevent water, produced from the exhaust system when the engine is started, from adhering to the sensor and damaging it.
Block Diagram
Operation
Pre-heater control
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The A/F sensor heater is operated at a duty ratio of approx. 15% within the specified time directly after the engine is started.
Normal control
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The PCM operates the A/F sensor based on the following control conditions:
|
Output duty ratio |
Control condition |
|
0% |
|
|
0?100% (Duty ratio determined by measuring the element temperature by the A/F sensor heater element impedance) |
|
Accelerator Pedal Position (App) Sensor
Purpose/Function
Detects the accelerator pedal depression amount as basic information for
mainly determining the throttle valve opening.
Detects the accelerator pedal depression amou ...
Air Fuel Ratio (A/F) Sensor Inspection
A/F Sensor Inspection
1. Connect the M-MDS to the DLC?2.
2. Switch the ignition ON (engine on).
3. Warm up the engine to normal operating temperature.
4. Access the following PIDs using the M-M ...
Other materials:
Manifold Absolute Pressure (Map) Sensor/Intake Air Temperature (Iat) Sensor
No.2 Removal/Installation
NOTE:
Because the IAT sensor No.2 is integrated in the MAP sensor, replacing the
IAT sensor No.2 includes replacement of the MAP sensor/IAT sensor No.2.
1. Disconnect the negative battery cable..
2. Disconnect the MAP sensor/IAT sensor No.2 connector.
3. Remove the MAP sensor/IA ...
Rear Seat Back Frame Removal/Installation
CAUTION:
When performing the procedure with a rear seat removed from the vehicle,
perform the procedure on a clean cloth so as not to damage or soil the seat.
6:4 Split Type
1. Remove the trunk board..
2. Remove the rear seat back..
3. Remove the headrest.
4. Open fasteners A ...
Front Door Latch Switch Inspection
1. Perform the front door glass preparation..
2. Disconnect the negative battery cable..
3. Remove the following parts:
a. Inner garnish.
b. Front door trim.
c. Front door glass.
d. Front door module panel.
e. Front door key cylinder.
f. Front door latch and lock actuator.
4. Verif ...
