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Engine Controls - Tests W/codes - 4-cyl Mazda 323 BG

Testing & Diagnostics 22 illustrations ~557 words

INTRODUCTION

Note. For MX-3 1.8L information, see TESTS W/CODES - 6-CYL article.

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed with self-diagnostics. If no fault codes or only pass codes are present after entering self-diagnostics, proceed to TESTS W/O CODES article for diagnosis by symptom (i.e. ROUGH IDLE, NO START, etc.).

HARD FAILURES

Hard failures cause CHECK ENGINE light to illuminate and remain on until problem is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined using diagnostic (code) charts. If a sensor fails, control unit will use a substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, the vehicle runs but driveability will not be optimum.

INTERMITTENT FAILURES

Intermittent failures may cause CHECK ENGINE light to flicker or illuminate and go out after the intermittent fault goes away. However, the corresponding trouble code will be retained in ECU memory. If related fault does not reoccur within a certain time frame, related trouble code will be erased from ECU memory. Intermittent failures may be caused by a sensor, connector or wiring related problems. See INTERMITTENTS in TESTS W/O CODES article.

Trouble Code Access

  1. Use Self Diagnostic Checker (49 H018 9A1) and System Selector (49 B019 9A0) to retrieve trouble codes. Connect one lead of self diagnostic checker to ground and the other to system selector. Connect system selector to data link connector. (Scheme 9)
  2. With ignition on and engine off, verify No. 88 flashes on display and buzzer sounds for 3 seconds. If No. 88 does not flash, check main relay, power supply circuit and connector wiring. Repair or replace as necessary. If No. 88 flashes and buzzer sounds for more than 20 seconds, check for short circuit between ECM terminal 1E and data link connector. Replace ECM as necessary and reconnect test equipment.
  3. Note trouble codes. Check «CODE CHARTS»(/mazda/323/bg-1989-1995/remont/testing-diagnostics/#engine-controls-tests-wcodes-4-cyl__trouble-code-charts) for possible cause. If more than one code is present, codes will be displayed in numerical order. Clear codes after repairs are complete. See «CLEARING CODES»(/mazda/323/bg-1989-1995/remont/testing-diagnostics/#engine-controls-tests-wcodes-4-cyl).

Scheme 9

Scheme 9

Clearing Trouble Codes

  1. Disconnect negative battery cable. Depress brake pedal for at least 5 seconds. Reconnect battery cable.
  2. Ground test connector with jumper wire. Turn ignition on, but do not start engine for 6 seconds. Start engine and run at 2000 RPM for 2 minutes. Verify no codes are displayed.

SUMMARY

If no hard fault codes (or only pass codes) are present, proceed to TESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.).

TROUBLE CODE CHARTS

Note. See PIN VOLTAGE CHART S article to identify ECU connector terminals.

Note. Trouble Codes 6, 12, 55, 60, 61, 62 and 63 are automatic transmission related problems.

Scheme 10

Scheme 10: TROUBLE CODE CHARTS

TROUBLE CODE IDENTIFICATION TABLE

DTCDescription
CODE 2NE Signal-Distributor
CODE 3G Signal-Distributor
CODE 8Airflow Meter
CODE 9Coolant Thermosensor
CODE 10Intake Air Thermosensor
CODE 12Throttle Sensor
CODE 14Atmospheric Pressure Sensor
CODE 15Oxygen Sensor
CODE 17Feedback System
CODE 25Pressure Regulator Solenoid Valve
CODE 26Purge Control Solenoid Valve
CODE 34Idle Speed Control
CODE 41Variable Inertia Charging System DOHC EX. MX-3

TROUBLE CODE IDENTIFICATION

Scheme 11

Scheme 11: CODE 2: NE SIGNAL-DISTRIBUTOR

Scheme 12

Scheme 12

Scheme 13

Scheme 13: CODE 3: G SIGNAL-DISTRIBUTOR

Scheme 14

Scheme 14

Scheme 15

Scheme 15: CODE 8: AIRFLOW METER

Scheme 16

Scheme 16

Scheme 17

Scheme 17: CODE 9: COOLANT THERMOSENSOR

Scheme 18

Scheme 18: CODE 10: INTAKE AIR THERMOSENSOR

Scheme 19

Scheme 19: CODE 12: THROTTLE SENSOR

Scheme 20

Scheme 20

Scheme 21

Scheme 21: CODE 14: ATMOSPHERIC PRESSURE SENSOR

Scheme 22

Scheme 22: CODE 15: OXYGEN SENSOR

Scheme 23

Scheme 23

Scheme 24

Scheme 24: CODE 17: FEEDBACK SYSTEM

Scheme 25

Scheme 25

Scheme 26

Scheme 26: CODE 25: PRESSURE REGULATOR SOLENOID VALVE

Scheme 27

Scheme 27

Scheme 28

Scheme 28: CODE 26: PURGE CONTROL SOLENOID VALVE

Scheme 29

Scheme 29: CODE 34: IDLE SPEED CONTROL

CODE 41: VARIABLE INERTIA CHARGING SYSTEM DOHC EX. MX-3

Note. The following Flow Chart is Courtesy of Mazda Motors Corp.

Trouble Code No. 41 Variable Inertia Charging System Dohc Ex. MX-3. Scheme 30

Scheme 30: Trouble Code No. 41 Variable Inertia Charging System Dohc Ex. MX-3

See also:
CODE CHARTS
CLEARING CODES
CODE 41