Engine Control System: Other Mazda 3 BK

Without Using the SST

Note. The PCM terminal voltage can vary with the conditions when measuring and changes due to aged deterioration on the vehicle, causing false diagnosis. Therefore determine comprehensively where the malfunction occurs among the input systems, output systems, and the PCM.

Scheme 582

Scheme 583

Scheme 584

Scheme 585

Scheme 586

Scheme 587

Scheme 588

Scheme 589

Shift solenoid A signal

PCM terminals

1B (+)-Negative battery terminal (-)

Oscilloscope setting

1. 5 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition

Scheme 590

1. 4GR

Shift solenoid B signal

PCM terminals

1C (+)-Negative battery terminal (-)

Oscilloscope setting

5 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition

1GR

Scheme 591

Shift solenoid C signal

PCM terminals

1. 1D (+)-Negative battery terminal (-)

Oscilloscope setting

1. 5 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition

Scheme 592

1. 1GR or 2GR

Pressure control solenoid (+) signal

PCM terminals

1G (+)-Negative battery terminal (-)

Oscilloscope setting

1. 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Scheme 593

1. All of the following conditions are met. Ignition switch is turned to the ON position. (engine off) P or N position CTP

Pressure control solenoid (-) signal

PCM terminals

1. 1H (+)-Negative battery terminal (-)

Oscilloscope setting

1. 200 mV/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Scheme 594

1. All of the following conditions are met. Ignition switch is turned to the ON position. (engine off) P or N position CTP

Vehicle speed signal (ATX)

PCM terminals

1. 1J (+)-Negative battery terminal (-)

Oscilloscope setting

1. 1 V/DIV (Y), 2.5 ms/DIV (X), DC range

Vehicle condition

Scheme 595

1. Vehicle speed is 32 km/h {20 mph}.

Vehicle speed signal (MTX)

PCM terminals

1J (+)-1N (-)

Oscilloscope setting

1. 1 V/DIV (Y), 10 ms/DIV (X), DC range

Vehicle condition

Scheme 596

1. Vehicle speed is 10 km/h {6.2 mph}.

Input/turbine speed sensor (+) signal

PCM terminals

1. 1M (+)-Negative battery terminal (-)

Oscilloscope setting

1. 500 mV/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Scheme 597

1. Idle after warm-up

Input/turbine speed sensor (-) signal

PCM terminals

1. 1Q (+)-Negative battery terminal (-)

Oscilloscope setting

1. 500 mV/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Scheme 598

1. Idle after warm-up

Cooling fan control signals

PCM terminals

1. 1W(+)-1AA(-)

Oscilloscope setting

1. 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Scheme 599

1. Idle after warm up (engine speed approx. 700 rpm, A/C ON)

APP signal

Accelerator pedal is released

Scheme 600

Accelerator pedal is depressed

PCM terminals

1. 1AL(+)-2AA(-)

Oscilloscope setting

1. 2.5 V/DIV (Y), 2 ms/DIV (X), DC range

Vehicle condition

Scheme 601

1. Ignition switch is turned to the ON position. (engine off)

HO2S (front) heater control signal (California emission regulation applicable model)

PCM terminals

2G(+)-2AA(-)

Oscilloscope setting

1. 5 V/DIV (Y), 50 ms/DIV (X), DC range

Vehicle condition

Scheme 602

1. Idle after warm up (engine speed approx. 650 rpm, no load)

HO2S (front) heater control signal (except for California emission regulation applicable model)

PCM terminals

2G(+)-2AA(-)

Oscilloscope setting

1. 5 V/DIV (Y), 125 ms/DIV (X), DC range

Vehicle condition

Scheme 603

1. Idle after warm up (engine speed approx. 650 rpm, no load)

CMP sensor signal

(+)

PCM terminals

1. 2U(+)-2AA(-)

Oscilloscope setting

1. 1 V/DIV (Y), 25 ms/DIV (X), DC range

Vehicle condition

Scheme 604

1. Idle after warm up (engine speed approx. 650 rpm, no load)

(-)

PCM terminals

1. 2V(+)-2AA(-)

Oscilloscope setting

1. 1 V/DIV (Y), 25 ms/DIV (X), DC range

Vehicle condition

Scheme 605

1. Idle after warm up (engine speed approx. 650 rpm, no load)

CKP sensor signal

(+)

PCM terminals

2Y(+)-2AA(-)

Oscilloscope setting

1. 2 V/DIV (Y), 10 ms/DIV (X), DC range

Vehicle condition

Scheme 606

1. Idle after warm up (engine speed approx. 650 rpm, no load)

(-)

PCM terminals

1. 2Z(+)-2AA(-)

Oscilloscope setting

1. 2 V/DIV (Y), 10 ms/DIV (X), DC range

Vehicle condition

Scheme 607

1. Idle after warm up (engine speed approx. 650 rpm, no load)

OCV signal

PCM terminals

2AF(+)-2AA(-)

Oscilloscope setting

1. 2.5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Scheme 608

1. Idle after warm up (engine speed approx. 650 rpm, no load)

HO2S (front) signal (except for California emission regulation applicable model)

PCM terminals

2AG(+)-2AA(-)

Oscilloscope setting

1. 0.2 V/DIV (Y), 500 ms/DIV (X), DC range

Vehicle condition

Scheme 609

1. Idle after warm up (engine speed approx. 650 rpm, no load)

Generator output voltage signal

PCM terminals

2AM (+)-2AA (-)

Oscilloscope setting

1. 2 V/DIV (Y), 2.5 ms/DIV (X), DC range

Vehicle condition

Scheme 610

1. Idle after warm up (engine speed approx. 650 rpm, no load)

Purge control signal

PCM terminals

1. 2AN (+)-Negative battery terminal (-)

Oscilloscope setting

1. 2 V/DIV (Y), 0.1 s/DIV (X), DC range

Vehicle condition

Scheme 611

1. Idle after warm-up

Generator field coil control signal

PCM terminals

2AQ(+)-2AA(-)

Oscilloscope setting

1. 0.5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Scheme 612

1. Idle after warm up (engine speed approx. 650 rpm, no load)

Fuel injection control

PCM terminals (California emission regulation applicable model)

Fuel injection No.1: 2AW(+)-1AZ(-)

Fuel injection No.2: 2AS(+)-1AZ(-)

Fuel injection No.3: 2AX(+)-1AZ(-)

Fuel injection No.4: 2AT(+)-1AZ(-)

PCM terminals (except for California emission regulation applicable model)

1. Fuel injection No.1: 2BB(+)-1AZ(-)
2. Fuel injection No.2: 2BC(+)-1AZ(-)
3. Fuel injection No.3: 2BD(+)-1AZ(-)
4. Fuel injection No.4: 2AZ(+)-1AZ(-)

Oscilloscope setting

1. 10 V/DIV (Y), 25 ms/DIV (X), DC range

Vehicle condition

Scheme 613

1. Idle after warm up (engine speed approx. 650 rpm, no load)

IGT1, IGT2, IG3, IG4 control signals

PCM terminals (California emission regulation applicable model)

IGT1 (No.1): 2BE(+)-1BC(-)

IGT2 (No.2): 2BF(+)-1BB(-)

IGT3 (No.3): 2BG(+)-1BB(-)

IGT4 (No.4): 2BH(+)-1BC(-)

PCM terminals (except for California emission regulation applicable model)

1. IGT1 (No.1): 2BE(+)-1BG(-)
2. IGT2 (No.2): 2BF(+)-1BC(-)
3. IGT3 (No.3): 2BG(+)-1BC(-)
4. IGT4 (No.4): 2BH(+)-1BG(-)

Oscilloscope setting

1. 10 V/DIV (Y), 25 ms/DIV (X), DC range

Vehicle condition

Scheme 614

1. Idle after warm up (engine speed approx. 650 rpm, no load)

Using SST (WDS or Equivalent)

Note. PIDs for the following parts are not available on this model. Go to the appropriate part inspection. CMP sensor (See CAMSHAFT POSITION (CMP) SENSOR INSPECTION .) Main relay (See RELAY INSPECTION .)

Scheme 615

Scheme 616

Scheme 617

Scheme 618

Scheme 619

Scheme 620

Scheme 621

Scheme 622

1. Connect the SST (WDS or equivalent) to the DLC-2.
2. Turn the ignition switch to ON position.
3. Measure the PID value. If PID value is not within the specification, follow the instructions in Action column. NOTE: The PID/DATA MONITOR function monitors the calculated value of the input/output signals in the PCM. Therefore, an output device malfunction is not directly indicated as a malfunction of the monitored value for the output device. If a monitored value of an output device is out of specification, inspect the monitored value of the input device related to the output control. The simulation items that are used in the ENGINE CONTROL SYSTEM OPERATION INSPECTION are as follows. ACCS, ALTF, ARPMDES, ECT_DSD, EVAPCP, FAN_DUTY, FP, FUELPW1, GENVDSD, HTR11, HTR12, IMRC, IMTV, INJ_1, INJ_2, INJ_3, INJ_4, LPS, SEGRP, SSA/SS1, SSB/SS2, SSC/SS3, SSD/SS4, SSE/SS5, VT ACT1, VT DUTY

Scheme 623

1. Connect the WDS or equivalent to the DLC-2.
2. Set up the WDS or equivalent (including the vehicle recognition).
3. Select "Module Programming".
4. Select "Programmable Module Installation".
5. Select "PCM" and perform procedures according to directions on the WDS or equivalent screen. NOTE: If the PCM is replaced with a new one, the PCM stores DTC P0602 and illuminates the MIL even though no malfunction is detected. This means the PCM has not been configured yet.
6. Retrieve DTC's by the WDS or equivalent, then verify that there in no DTC present. If DTC is present, perform applicable DTC inspection. (See DTC TABLE .)

Open circuit

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. ECT sensor terminal A and PCM terminal 2AK ECT sensor terminal B and PCM terminal 2AA

Short circuit

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. ECT sensor terminal A and power supply ECT sensor terminal A and body GND ECT sensor terminal B and power supply

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. CKP sensor terminal A and PCM terminal 2Y CKP sensor terminal B and PCM terminal 2Z

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. CKP sensor terminal A and power supply CKP sensor terminal A and body GND CKP sensor terminal B and power supply CKP sensor terminal B and body GND

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. CMP sensor terminal A and PCM terminal 2V CMP sensor terminal B and PCM terminal 2U

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. CMP sensor terminal A and power supply CMP sensor terminal A and body GND CMP sensor terminal B and power supply CMP sensor terminal B and body GND

Scheme 624

1. Remove the battery cover.
2. Disconnect the negative battery cable.
3. Remove the plug hole cover. CAUTION: When replacing the CMP sensor, make sure there is no foreign material on it such as metal shavings. If it is installed with foreign material, the sensor output signal will malfunction resulting from fluctuation in magnetic flux and cause a deterioration in engine control.
4. Disconnect the CMP sensor connector.
5. Remove the CMP sensor installation bolt.
6. Remove the CMP sensor from the cylinder head cover.
7. Install in the reverse order of removal. Tightening torque 5.5-7.5 N.m {56-76 kgf.cm, 49-66 in.lbf}

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. Variable tumble shutter valve switch terminal A and PCM terminal 2W Variable tumble shutter valve switch terminal B and PCM terminal 2AA Variable tumble shutter valve switch terminal C and PCM terminal 2AE

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Variable tumble shutter valve switch terminal A and power supply Variable tumble shutter valve switch terminal A and body GND Variable tumble shutter valve switch terminal B and power supply Variable tumble shutter valve switch terminal C and power supply Variable tumble shutter valve switch terminal C and body GND

1. If there is no continuity in the following wiring harnesses, there is an open circuit. Repair or replace the wiring harness. Throttle body terminal A and PCM terminal 2M Throttle body terminal B and PCM terminal 2K Throttle body terminal C and PCM terminal 2I Throttle body terminal D and PCM terminal 2O

1. If there is continuity in the following wiring harnesses, there is a short circuit. Repair or replace the wiring harness. Throttle body terminal B and body ground Throttle body terminal B and power supply Throttle body terminal C and body ground Throttle body terminal C and power supply Throttle body terminal D and body ground Throttle body terminal D and power supply

1. If there is no continuity in the following wiring harnesses, there is an open circuit. Repair or replace the wiring harness. APP sensor terminal A and PCM terminal 1AE APP sensor terminal B and PCM terminal 1Y APP sensor terminal C and PCM terminal 1AA APP sensor terminal D and PCM terminal body ground APP sensor terminal E and PCM terminal 1AL APP sensor terminal F and PJB (California emission regulation applicable model) APP sensor terminal F and main relay terminal E (except for California emission regulation applicable model)

1. If there is continuity in the following wiring harnesses, there is a short circuit. Repair or replace the wiring harness. APP sensor terminal D and body ground APP sensor terminal D and power supply APP sensor terminal A and body ground APP sensor terminal A and power supply APP sensor terminal F and body ground APP sensor terminal F and power supply APP sensor terminal C and body ground APP sensor terminal C and power supply

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. MAF sensor terminal A and main relay terminal E MAF sensor terminal B and PCM terminal 1BD MAF sensor terminal C and PCM terminal 1AC

Scheme 625

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. MAF sensor terminal A and body GND MAF sensor terminal C and power supply MAF sensor terminal C and body GND MAF sensor terminal B and power supply

California Emission Regulation Applicable Model

Note. Before performing the following inspection, make sure to follow the troubleshooting flowchart. (See FOREWORD .)

Scheme 626

1. Warm up the engine to normal operating temperature.
2. Using the WDS or equivalent, monitor the following: Vehicle speed (PID: VSS) Engine speed (PID: RPM) Front HO2S Current (PID: O2S11)
3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.
4. Verify that the front HO2S current (PID: O2S11) is 0.25 mA or more while decelerating as shown in the figure. If not within the specification, inspect the HO2S for an open or short circuit. (See «Front HO2S circuit open/short inspection (sensor)»(ref-177569-S27686116582005060200000) .) Then if there is no malfunction in the wiring harness, replace the front HO2S.

Scheme 627

1. Disconnect the front HO2S connector.
2. Measure the resistance between front HO2S terminals C and D. If not within the specification, replace the front HO2S. (See «HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION»(ref-177569-S18346892032005060200000) .) Front HO2S heater resistance 1-10 ohms [20 °C {68 °F}]

Except for California Emission Regulation Applicable Model

Note. Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart.

Scheme 628

1. Warm up the engine to normal operating temperature.
2. Using the WDS or equivalent, monitor the following: Vehicle speed (PID: VSS) Engine speed (PID: RPM) Front HO2S Current (PID: O2S11)
3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.
4. Verify that the front HO2S outputs a voltage of 0.6 V or more, one time or more, then verify that the front HO2S current (PID: O2S11) is 0.3 V or less while decelerating as shown in the figure. If not within the specification, inspect the HO2S for an open or short circuit. (See «Front HO2S circuit open/short inspection (sensor)»(ref-177569-S27686116582005060200000) .) Then if there is no malfunction in the wiring harness, replace the front HO2S.

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. HO2S terminal A and PCM terminal 2AG HO2S terminal B and PCM terminal 2AA

Scheme 629

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. HO2S terminal A and body GND HO2S terminal A and power supply HO2S terminal B and power supply

Scheme 630

1. Disconnect the front HO2S connector.
2. Measure the resistance between front HO2S terminals C and D. If not within the specification, replace the front HO2S. Front HO2S heater resistance 2-50 ohms

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. HO2S terminal C and main relay terminal E HO2S terminal D and PCM terminal 2G

Scheme 631

Scheme 632

1. If there is no continuity, there is a short circuit. Repair or replace the wiring harness. Front and rear HO2S terminal C and body GND HO2S terminal D and power supply HO2S terminal D and body GND

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. HO2S terminal A and PCM terminal 2AH HO2S terminal B and PCM terminal 2AA

Scheme 633

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. HO2S terminal A and body GND HO2S terminal A and power supply HO2S terminal B and power supply

Scheme 634

1. Disconnect the middle HO2S connector.
2. Measure the middle HO2S resistance between terminals C and D. If not within the specification, replace the middle HO2S.

1. Middle HO2S heater resistance 2-50 ohms

Note. Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart.

Scheme 635

1. Warm up the engine to normal operating temperature.
2. Using the WDS or equivalent, monitor the following: Vehicle speed (PID: VSS) Engine speed (PID: RPM) Rear HO2S Current (PID: O2S13)
3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.
4. Verify that the rear HO2S outputs a voltage of 0.6 V or more, one time or more, then verify that the rear HO2S current (PID: O2S13) is 0.3 V or less while decelerating as shown in the figure. If not within the specification, inspect the HO2S for an open or short circuit. (See «Rear HO2S circuit open/short inspection (sensor)»(ref-177569-S02686578212005060200000) .) Then if there is no malfunction in the wiring harness, replace the rear HO2S.

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. HO2S terminal A and PCM terminal 2AD HO2S terminal B and PCM terminal 2AA

Scheme 636

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. HO2S terminal A and body GND HO2S terminal A and power supply HO2S terminal B and power supply

Scheme 637

1. Disconnect the rear HO2S connector.
2. Measure the rear HO2S resistance between terminals C and D. If not within the specification, replace the rear HO2S. Rear HO2S heater resistance 2-50 ohms

Note. Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart.

Scheme 638

1. Warm up the engine to normal operating temperature.
2. Using the WDS or equivalent, monitor the following: Vehicle speed (PID: VSS) Engine speed (PID: RPM) Rear HO2S Current (PID: O2S12)
3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.
4. Verify that the rear HO2S outputs a voltage of 0.6 V or more, one time or more, then verify that the rear HO2S current (PID: O2S12) is 0.3 V or less while decelerating as shown in the figure. If not within the specification, inspect the HO2S for an open or short circuit. (See «Rear HO2S circuit open/short inspection (sensor)»(ref-177569-S02686578212005060200000) .) Then if there is no malfunction in the wiring harness, replace the rear HO2S.

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. HO2S terminal A and PCM terminal 2AH HO2S terminal B and PCM terminal 2AA

Scheme 639

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. HO2S terminal A and body GND HO2S terminal A and power supply HO2S terminal B and power supply

Scheme 640

1. Disconnect the rear HO2S connector.
2. Measure the rear HO2S resistance between terminals C and D. If not within the specification, replace the rear HO2S. Rear HO2S heater resistance 2-50 ohms

1. If there is no continuity, there is an open circuit. Repair or replace the wiring harness. HO2S terminal C and main relay terminal E HO2S terminal D and PCM terminal 2C

Scheme 641

Scheme 642

1. If there is no continuity, there is a short circuit. Repair or replace the wiring harness. Front and rear HO2S terminal C and body GND HO2S terminal D and power supply HO2S terminal D and body GND

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. MAP sensor terminal C and power supply. MAP sensor terminal C and body GND. MAP sensor terminal D and power supply. MAP sensor terminal D and body GND

Scheme 643

1. Remove the battery cover.
2. Disconnect the negative battery cable.
3. Remove the plug hole cover.
4. Remove the vacuum hose.
5. Disconnect the MAP sensor connector.
6. Remove the MAP sensor installation screw.
7. Remove MAP sensor from the intake manifold.
8. Install in the reverse order of removal. Tightening torque 2.7-3.7 N.m {28-37 kgf.cm, 24-32 in.lbf}

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Knock sensor terminal A and power supply Knock sensor terminal A and body GND Knock sensor terminal B and power supply Knock sensor terminal B and body GND

Scheme 644

1. Remove the following part for easier access. Intake manifold (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF] , INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3] .)
2. Disconnect the KS connector.
3. Remove the KS installation bolt, then remove the KS.
4. Install in the reverse order of removal. Tightening torque 16-24 N.m {1.7-2.4 kgf.m, 12-17 ft.lbf}

Scheme 645

Scheme 646

1. Remove the battery cover.
2. Disconnect the negative battery cable.
3. Remove the plug hole cover.
4. Remove the battery duct.
5. Remove in the order indicated in the table.
6. Install in the reverse order of removal.

1. If there is continuity, there is a short circuit. Repair or replace the wiring harness. Barometric pressure sensor terminal C and power supply. Barometric pressure sensor terminal C and body GND. Barometric pressure sensor terminal A and power supply. Barometric pressure sensor terminal A and body GND