Diagnosis - LA4A-EL: Overview Mazda 626 GF

DESCRIPTION & OPERATION

Input signals from sensors are sent to the Powertrain Control Module (PCM). The PCM controls shift or converter clutch application. The PCM can also determine line pressure needed to optimize shift feel. PCM has built-in self-diagnosis, fail-safe code and warning code display for the main input sensors and solenoid valves. Five electronic solenoids accomplish the following functions

1. 2 On/Off solenoids for shifting.
2. One Pulse-Width Modulator (PWM) solenoid for Torque Converter Clutch (TCC) control.
3. One Electronic Pressure Control (EPC) solenoid for line pressure control.
4. One 3-2 timing/coast clutch solenoid to control release of coast clutch, coordinated release of the direct clutch, and apply of the low and intermediate band.

Description

Following procedures are functional tests of EEC-V system. These basic test steps must be followed in sequence to avoid misdiagnosis

1. Visual Check
2. Equipment Hookup
3. KOEO (Key On Engine Off) SELF-TEST
4. KOER (Key On Engine Running) SELF-TEST
5. Computed Timing Check
6. Continuous Memory Self-Test

After each service or repair procedure has been completed, repeat QUICK TEST to ensure all EEC-V systems work properly and diagnostic trouble codes are no longer present.

Generic OBD-II Parameter Identification (PID)

Turn ignition switch to OFF position. Ensure test equipment is properly attached. Program scan tester using the following steps

1. Select vehicle and engine selection menu (optional). (Схема №6)
2. Select year, engine, model and any additional information requested by scan tester (optional).
3. Select GENERIC OBD-II OPTIONS. Press CONT button if monitors are not complete.
4. Select PID/DATA MONITOR AND RECORD.
5. Turn ignition on or start engine and allow to idle.
6. Follow operating instructions from scan tester menu.
7. Select PIDs and press START.

Non-Generic OBD-II Parameter Identification (PID)

Turn ignition switch to OFF position. Ensure test equipment is properly attached. Program scan tester using the following steps

1. Select vehicle and engine selection menu. (Схема №6)
2. Select year, engine, model and any additional information requested by scan tester.
3. Select GENERIC OBD-II OPTIONS. Press CONT button if monitors are not complete.
4. Select DIAGNOSTIC DATA LINK.
5. Select PCM - POWERTRAIN CTRL MODULE.
6. Select DIAGNOSTIC TEST MODES.
7. Select PID DATA MONITOR AND RECORD.
8. Turn ignition on or start engine and allow to idle.
9. Follow operating instructions from scan tester menu.
10. Select PIDs and press START.

On-Board System Readiness (OSR) Test Mode

All OBD-II scan testers must display OSR test. The OSR will display monitors on the vehicle and status of all monitors; complete or not complete. If not complete, the scan tester will display which monitor has not completed. To enter OSR, turn ignition switch to OFF position. Ensure test equipment is properly attached. Program scan tester using the following steps

1. Select vehicle and engine selection menu (optional). (Схема №6)
2. Select year, engine, model and any additional information requested by scan tester.
3. Follow operating instructions from scan tester menu.
4. Select GENERIC OBD-II FUNCTIONS. Press TEST button if all OBD-II monitors are not complete.
5. Start engine and allow to idle.
6. Select ON-BOARD SYSTEM READINESS.

Hardware Limited Operational Strategy (HLOS)

If a number of system or sensor failures are present and PCM is not receiving enough information to operate, PCM will switch to HLOS mode. PCM will output fixed values to allow operation of vehicle. Driveability concerns will be present. PCM will not output diagnostic trouble codes in this mode.