Part 2
ENGINE CONTROL SYSTEM OPERATION INSPECTION [13B-MSP]
Part 2
Continued From Part 1 Part 1
Jet Air Fuel Mixing System Operation Inspection
NOTE:
- When the hose and/or nozzle of the jet air fuel mixing system are clogging, the engine has rough-idle.
1. Verify that the jet air fuel mixing system hose is connected properly, according to INTAKE-AIR SYSTEM VACUUM HOSE ROUTINE DIAGRAM. Intake-Air System Vacuum Hose Routing Diagram
- If the hose is not connected properly, connect the hose properly.
2. Verify that there is no collapse, crack and divide in each intake-air system hoses.
- If there is collapse, crack or divide, repair or replace suspected part.
3. Verify that there is no collapse, crack and divide between air hose and jet air fuel mixing pipe.
- If there is collapse, crack or divide, repair or replace suspected part.
4. Perform the Intake Manifold Vacuum Inspection. (See Intake Manifold Vacuum Inspection)
- If there is malfunction, repair or replace suspected part, according to inspection results.
5. Connect the M-MDS to DLC-2.
6. Monitor following PIDs.
- MAF (MAF sensor)
- ETC_DSD (target throttle valve opening angle)
7. Measure the air flow amount for jet air fuel mixing nozzle according to following "Nozzle air flow amount measurement procedure".
- If there is no air flow, remove the objection for following points;
- Jet air fuel mixing nozzle
- Hose between jet air fuel mixing nozzle and air hose
Nozzle air flow amount measurement procedure
1. Start the engine and warm up it to normal operating temperature.
2. Set the throttle valve opening angle to 1.5-2.0 ° using the M-MDS simulation function PID ETC_DSD.
3. Monitor the PID MAF value and record it as "MAF A".
4. Pick the hose between jet air fuel mixing nozzle and air hose with Step 2 condition.
5. Monitor the PID MAF value and record it as "MAF B" with Step4.
6. Calculate the nozzle air flow amount using the following formula.
- "Nozzle air flow amount" = "MAF A" - "MAF B"
Fuel Injector Operation Inspection
Fuel injector (FP) (RP) operation inspection
1. Start the engine and let it at idle.
2. Inspect fuel injector control signal wave profile at the following PCM terminals.
PCM Inspection
- Terminal 2BB (FP)
- Terminal 2BD (RP)
3. If not as specified, inspect the following and repair or replace defective parts.
Front rotor:
- Open circuit in wiring between fuel injector (FP) terminal A and main relay terminal C
- Open or short circuit in wiring between fuel injector (FP) terminal B and PCM terminal 2BB
- Open or short internal circuit or fuel injector (FP)
Rear rotor:
- Open circuit in wiring between fuel injector (RP) terminal A and main relay terminal C
- Open or short circuit in wiring between fuel injector (RP) terminal B and PCM terminal 2BD
- Open or short internal circuit of fuel injector (RP)
Fuel injector (FS) (RS) operation inspection
1. Connect the M-MDS to the DLC-2.
2. Start the engine and let it at idle.
3. Access the RPM PID.
4. Verify that the fuel injector control wave is not outputted at the following PCM terminal.
PCM Inspection
- Terminal 2BC (FS)
- Terminal 2AZ (RS)
5. If the fuel injector control signal is outputted, inspect the following and repair or replace defective parts.
- MAF sensor
- TP sensor
- IAT sensor
6. Inspect the fuel injector control signal wave profile at the following PCM terminals while the RPM PID is 5,000 rpm or over.
PCM Inspection
- Terminal 2BC (FS)
- Terminal 2AZ (RS)
7. If not as specified, inspect the following and repair or replace defective parts.
Front rotor:
- Open circuit in wiring between fuel injector (FS) terminal A and main relay terminal C
- Open or short circuit in wiring between fuel injector (FS) terminal B and PCM terminal 2BC
- Open or short internal circuit of fuel injector (FS)
Rear rotor:
- Open circuit in wiring between fuel injector (RS) terminal A and main relay terminal C
- Open or short circuit in wiring between fuel injector (RS) terminal B and PCM terminal 2AZ
- Open or short internal circuit or fuel injector (RS)
Fuel Pump Operation Inspection
CAUTION:
- Connecting the wrong check connector terminal may possibly cause malfunction. Carefully connect the specified terminal only.
1. Short the check connector terminal F/P to the body GND using a jumper wire.
2. Remove the fuel-filler cap.
3. Turn the ignition switch to the ON position.
4. Verify that the fuel pump operation sound is heard.
- If no operation sound heard, proceed to next step.
5. Measure the voltage at the wiring harness side fuel pump connector terminal B.
Specification
- 8.0-11.5 V (Ignition switch at on)
- If the voltage is as specified, inspect the following:
- Fuel pump continuity
- Fuel pump GND
- Wiring harness between fuel pump relay and PCM terminal 1H
- If not as specified, inspect the following:
- Fuel pump relay
- Fuel pump resister
- Wiring harness and connector (Main relay -fuel pump relay-fuel pump resister - fuel pump)
Fuel Pump Control System Inspection
1. Crank the engine and verify that the fuel pump relay operation sound is heard.
2. If the operation sound is not heard, inspect the following:
- Fuel pump relay
- Wiring harness and connectors (Main relay- fuel pump relay-PCM terminal 1H)
Fuel Pump Speed Control Operation Inspection
1. Perform the fuel pump operation inspection.
2. Verify that fuel pump speed control relay operation sound is heard, while cranking the engine.
- If operation sound is not heard, inspect the following:
- Fuel pump speed control relay
- Wiring harnesses and connectors (Main relay-fuel pump speed control relay-PCM terminal 1K)
3. Remove the fuel-filler cap.
4. Verify that the fuel pump unit operation sound frequency at cranking is higher than during idle.
- If it cannot verified, inspect for the following:
- Fuel pump resister
- Fuel pump speed control relay
- Wiring harnesses and connectors (open circuit at fuel pump relay terminal C-fuel pump terminal B)
Spark Test
1. Release the fuel line pressure. Before Service Precaution
2. Remove the fuel pump relay.
3. Verify that each high-tension lead and the connector is connected properly.
4. Inspect the ignition system using the following procedure:
WARNING:
- High voltage in the ignition system can cause strong electrical shock which can result in serious injury. Avoid direct contact to the vehicle body during the following spark test.
Step 1-Step 7:
5. Install the fuel pump relay.
Cooling Fan Control System Inspection
1. Connect the M-MDS to the DLC-2.
2. Verify that DTC P0480, P0481 or P0482 is not displayed.
- If DTC P0480, P0481 or P0482 are displayed, perform DTC inspection. DTC Table [Engine]
3. Start the engine and run it at idle with ECT PID is below 94 °C {201 °F}.
4. Verify that both cooling fan No.1 and No.2 do not operate when the A/C and fan switch is off.
- If the cooling fan No.1 and No.2 operate low speed, inspect for following;
- Cooling fan relay No.1 (stuck close)
- Cooling fan relay No.5 (stuck close)
- If the cooling fan No.1 does not operate but the cooling fan No.2 operates middle speed, inspect for following;
- Cooling fan relay No.3 (stuck close)
- Cooling fan relay No.4 (stuck close)
5. Start the engine and run it at idle with the ECT is 97-100 °C {207-212 °F}.
6. Verify that both cooling fan No.1 and No.2 operate low speed.
- If the operation can not be verified, inspect the following points according to cooling fan conditions.
7. Start the engine and run it idle with the ECT is 101-107 °C {214-224 °F}.
8. Verify that both cooling fan relay No.1 and No.2 operate middle speed.
- If the operation can not be verified, inspect the following points according to cooling fan conditions.
9. Stop the engine.
10. Disconnect the ECT sensor connector.
11. Turn the ignition switch to ON position.
12. Verify that both cooling fan No.1 and No.2 operate high speed.
- If the operation can not be verified, inspect the following points according to cooling fan conditions.
13. Clear the DTC from the PCM memory using the M-MDS. After Repair Procedure
Secondary Air Injection (AIR) System Inspection
1. Connect the M-MDS to the DLC-2.
2. Verify that DTC P2257, P2258, P2259 or P2260 is not displayed.
- If DTC P2257, P2258, P2259 or P2260 are displayed, perform DTC inspection.
DTC Table [Engine]
3. Access the ECT PID.
4. Start the engine and warm it up to the normal operating temperature.
5. Cool down the engine to that the ECT PID is 30°C {86°F} or less.
6. Turn the ignition switch to the ON position.
7. Verify that the PCM terminal 1G voltage is B+ and the AIR pump is not operating.
- If the PCM terminal 1G voltage is not B+, inspect and repair or replace open or short circuit between PCM terminal 2G and AIR solenoid valve connector B.
- If the AIR pump is operating inspect for the following:
- AIR pump relay (stuck closed)
- Wiring harnesses and connectors (Main relay terminal C-AIR pump relay-PCM terminal 1G/AIR PUMP fuse-AIR pump relay-AIR pump)
8. Start the engine.
9. Verify that the AIR pump is operating and the PCM terminal 1G voltage is 0 V after the engine is started.
- If the AIR pump does not operate, inspect for the following:
- AIR pump relay (stuck open)
- AIR pump (internal malfunction)
- Wiring harnesses and connectors (Main relay terminal C-AIR pump relay-PCM terminal 1G/AIR PUMP fuse-AIR pump relay-AIR pump-GND)
- If PCM terminal 1G voltage is not 0 V, inspect and repair or replace open or short circuit between PCM terminal 2G and AIR solenoid valve connector B.
- If the AIR pump operates and PCM terminal 1G is 0 V, inspect for the following:
- AIR pump (pressure)
- AIR solenoid valve (stuck or closed)
- Vacuum hose (Intake manifold-vacuum tank-AIR solenoid valve - AIR control valve)
- Secondary air passage (AIR pump-AIR control valve-exhaust manifold)
Metering Oil Pump Control Inspection
1. Verify that the engine oil level is within the normal range.
2. Connect the M-MDS to the DLC-2.
3. Race the engine after 90 s or more have elapsed since the engine was started and warmed up. (Maintain engine speed at 4,000 rpm for approx. 10 s)
4. Verify that DTC P0522, P0523, P1680, P1681, P1682, P1683, P1684, P1685, P1686 or P1687 is not displayed.
- If DTCs are displayed, perform DTC inspection. DTC Table [Engine]
Purge Control System Inspection
1. Start the engine.
2. Disconnect the vacuum hose at quick release connector.
3. Put a finger to the purge solenoid valve and verify that there is no vacuum applied when the engine is cold.
- If there is vacuum, inspect the following:
- Wiring harness and connectors (Purge solenoid valve-PCM terminal 2C)
- Purge solenoid valve
4. Warm up the engine to the normal operating temperature.
5. Stop the engine.
6. Connect the M-MDS to the DLC-2 and verify that the DTC P0443 is shown. Perform the DTC inspection. DTC Table [Engine]
7. Turn the ignition switch to the ON position.
8. Select the ECT PID.
9. Verify that the engine is warmed up completely.
- If the engine is not warmed up completely, perform the ECT sensor inspection.
10. Set the vehicle on the dynamometer or chassis roller.
WARNING:
- When the dynamometer or chassis roller is operating, there is a possibility that the operator may come into contact with or be caught up in the rotating parts, leading to serious injuries or death. When performing work while the dynamometer or chassis roller is operating, be careful not to come into contact with or be caught up in any of the rotating parts.
11. Drive the vehicle at an engine speed of approx. 2000 rpm for 30 s or more.
12. Put a finger to the purge solenoid valve and verify that there is no vacuum applied during above step 2.
- If there is no vacuum, inspect the following:
- Wiring harness and connector (Main relay - purge solenoid valve-PCM terminal 2C)
- Purge solenoid valve
- MAF, APP1, APP2, TP_REL and LOAD PIDs
- If there is vacuum, inspect the following:
- Vacuum hose (Purge solenoid valve-charcoal canister)
A/C Cut-off Control System Inspection
1. Start the engine.
2. Turn the A/C switch and fan switch on.
3. Verify that the A/C compressor magnetic clutch actuates.
- If it does not actuate, go to the symptom troubleshooting "No.23 A/C does not work sufficiently".
No.23 A/C Does Not Work Sufficiently
4. Fully open the throttle valve and verify that the A/C compressor magnetic clutch does not actuate for 2-5 s.
- If it actuates, inspect as follows:
- A/C relay
- Open or short to GND circuit in wiring harness and connectors (Ignition switch-A/C relay-PCM terminal 1I)
- A/C related parts
- APP1, APP2 PIDs
Variable Fresh Air Duct (VFAD) Control System Operation Inspection (With VFAD)
1. Connect the M-MDS to the DLC-2.
2. Access the RPM PID.
3. Start the engine.
4. Inspect shutter valve operation under the following conditions. VFAD shutter valve operation
- If the shutter valve operation is not as specified, inspect VFAD solenoid valve. Testing and Inspection
- If the VFAD solenoid valve is not normal, replace VFAD solenoid valve.
- If the VFAD solenoid valve is normal, inspect the following:
- Open or short circuit PCM terminal 1AE and VFAD solenoid valve terminal B
- Open or short circuit main relay and VFAD solenoid valve terminal B
- Vacuum hose looseness or damage
- Vacuum chamber cracked or damaged
- Shutter valve actuator
Testing and Inspection
- Shutter valve is stuck open or closed.
Evaporative Emission (EVAP) System Leak Inspection
- To verify that the problem has been fixed properly after repairs, the run drive cycle or EVAP system leak inspection must be performed.
EVAP system leak inspection using M-MDS
NOTE:
EVAP system test outline
- The EVAP system test, which can substituted for the run drive cycle as an EVAP control system repair confirmation method, can be done while operating the M-MDS in the KOEO (Key On Engine Off) condition instead of actually driving the vehicle.
EVAP system test description
- The EVAP system test finds gas leaks in the system using the PCM to monitor changes in the air pump load current of the EVAP system leak detection pump. This test starts after sending an on-demand test signal from the M-MDS to the PCM. The PCM controls the air pump and change-over-valve operation and also stores the load current of the air pump as follows:
- The PCM commands turn the air pump on and retrieve the air pump load current value (LDP_MON PID) as a reference current (LDP_REF PID).
- After retrieving a reference current value, the PCM commands the change-over-valve to open, then captures the air pump load current value (LDP_MON PID) as idle current (LDP_IDL PID). The EVAP system will be pressurized from this phase.
- The PCM continues to monitor the air pump load current value (LDP_MON PID) until the end of the test.
- You can confirm whether any evaporative gas leak occurred or not by reading the test results.
EVAP system malfunction judgment
- The PCM calculates the stored air pump load current value and send the results to the M-MDS as DTCs:
P0442-P2407:
Evaporative system test procedure
1. Select the EVAP system test from the Toolbox on the M-MDS display and follow the instructions.
2. Verify that all of the following PIDs are within the specifications at the pre-test confirmation screen.
NOTE:
- To successfully perform this procedure, all PIDs must be within the following specifications before proceeding to the next step.
- The PCM will cancel the EVAP system test if the VPWR PID value falls lower than 11.0 V during the test.
Specification
3. Start the engine.
4. Drive the vehicle or let the engine idle more than 20 min.
5. Turn ignition switch off, then turn it to the ON position again (Key On Engine Off).
6. Press the tick icon to start the test.
7. Verify that no DTCs present after the completion of the test.
- If any test result is indicated with red, diagnose the problem using the following DTC troubleshooting procedure or component inspection procedure.
- If any DTCs are detected, diagnose the problem using the appropriate DTC troubleshooting procedure.
EVAP system leak inspection using leak tester
1. Perform the following SST (Evaporative Emission System Tester 134-01049) self-test:
NOTE:
- If the tester does not work correctly during the self-test, refer to the tester operators manual for a more detailed self-test procedure.
a. Verify that the control valve on the panel is in the HOLD position then open the nitrogen bottle valve.
b. Connect the vehicle interface hose (part of the SST) to the SELF-TEST port located on the control panel. Hand tighten the fitting. (Do not overtighten.)
c. Turn the control valve to the TEST position.
d. The gauge should read 331-381 mm {13-15 in} of water.
- If the gauge is not reading in this range, adjust the pressure by turning the black knob on the low pressure regulator at the nitrogen bottle.
e. Turn the control valve to the HOLD position.
f. Verify that the gauge holds pressure and that the flow meter reads no flow.
1 If there is no drop in pressure and no flow, the tester passes the self-test.
2 If the gauge leaks down, refer to the tester operators manual.
2. Connect the SST to the vehicle.
a. Verify that the control valve on the panel is in the HOLD position then open the nitrogen bottle valve.
b. Remove the fuel-filler cap from the vehicle.
- If the fuel-filler cap is not a MAZDA part or equivalent, replace it.
c. Connect the receiver assembly (SST: 134-01059) to the vehicle cap test hose assembly (part of the SST) and the fuel-filler cap from the vehicle.
d. Connect the cap adaptor (SST: 134-01058) to the vehicle cap test hose assembly (part of the SST) and to the fuel-filler neck.
e. Connect the vehicle interface hose (part of the SST) to the center fitting of the vehicle cap test hose assembly (part of the SST).
3. Connect the M-MDS to the DLC-2.
4. Turn the ignition switch to the ON position (Engine off).
5. Request the PCM on-board device control (Mode 08) using the M-MDS to close the change-over valve (COV) in the EVAP system leak detection pump.
NOTE:
- The COV is closed for 10 min unless the following any actions are done:
- The engine is started.
- The ignition switch is turned off position.
6. Make sure the control valve on the 134-01049 is in the HOLD position and that the valve on the cylinder of nitrogen gas is open.
7. Turn the control valve to the open position and let the system fill. You should note a drop in the gauge pressure along with the flow meter being pegged at maximum flow for several minutes depending on how full or empty the fuel tank is, and how long it takes to completely fill and pressurize the evaporative emissions system hoses.
8. If the gauge and the flow meter do not settle to a measurable level after 2-3 min, then refer to the appropriate service information to verify that the cut or vent valve is properly closed.
9. Verify the pressure gauge and flow meter reading to determine if there is an evaporative emissions leak:
NO EVAPORATIVE LEAK:
- The flow meter registers "zero flow" and the pressure gauge returns to the pre-set pressure of 356 mm {14 in} of water (H2O).
EVAPORATIVE LEAK:
- The pressure does not return to the preset level of 356 mm {14 in} of water (H2O) when measuring the flow. See "SETTING LEAK STANDARD FOR TESTING" (.020 to.040 inch H2O) of the Evaporative Emissions Tester operators manual (134-01067).
NOTE:
1 Turn the control valve to the HOLD position then disconnect the SST.
Rotor Balance Test
WARNING:
- High-voltage in the ignition system can cause strong electrical shock which can result in serious injury. Avoid direct contact to the vehicle body during the rotor balance test.
- High-voltage spark will negatively effect the engine control. To prevent this, the high-tension leads keep away from sensors and wiring harnesses.
CAUTION:
- If the rotor balance test is performed over a long period of time, it may cause overheating or damage to the catalytic converter. Be very careful when performing the rotor balance test.
NOTE:
- The purpose of the rotor balance test is to find weak or non-contributing rotors. In this test, the high-tension leads are disconnected one by one to shut off the ignition on each rotor with the engine running. By carrying out the rotor balance test, a total determination of the compression pressure, air/fuel mixture, and ignition is possible.
1. Connect the M-MDS to the DLC-2.
2. Access the RPM PID.
3. Start the engine.
4. Remove high-tension lead from each rotor and monitor the RPM PID value.
5. If the RPM PID does not drop, inspect the following:
- Fuel injector (FP) (RP)
- Spark plugs
- High-tension leads
- Ignition coil
- Compression pressure