Inspection Procedure 5
INSPECTION PROCEDURE 5: Cranks, Won't StartCRANKS, WON'T START CIRCUIT
- Refer to MFI, Ignition circuit. Inspection Procedure 32
CIRCUIT OPERATION
- Refer to MFI, Ignition circuit. Inspection Procedure 32
COMMENT
- In cases such as the above, the cause is probably no spark, fuel delivery, or fuel quality problems. In addition, foreign materials (water, kerosene, etc.) may be mixed with the fuel.
TROUBLESHOOTING HINTS (The most likely causes for this case:)
- Malfunction of the ignition system.
- Malfunction of the fuel pump system.
- Malfunction of the injector system.
- Malfunction of the ECM [M/T] or the PCM [A/T].
- Contaminated fuel.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
STEP 1. Measure the battery positive voltage.
1. Measure the battery positive voltage during cranking.
- The voltage should remain greater than 8 volts while the engine is cranked.
Q: Does the voltage remain greater than 8 volts while the engine is cranked?
YES : Go to Step 2.
NO : Check the battery. Refer to chassis electrical, Battery - Battery check. Then confirm that the malfunction symptom is eliminated.
STEP 2. Check the timing belt for breaks.
Q: Is the timing belt good condition?
YES : Go to Step 3.
NO : Replace timing belt. Then confirm that the malfunction symptom is eliminated.
STEP 3. Using scan tool MB991958, read the diagnostic trouble code (DTC).
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Read the DTC.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Refer to MFI, Diagnostic Trouble Code Chart. Diagnostic Trouble Code Descriptions
NO : Go to Step 4.
STEP 4. Using scan tool MB991958, check data list.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check the following items in the data List. Refer to MFI, Data List Reference Table. Datal List Reference Table
a. Item 1: Power Supply Voltage.
b. Item 2: Crankshaft Position Sensor.
c. Item 6: Engine Coolant Temperature Sensor.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Are they operating properly?
YES : Go to Step 5.
NO : Repair or replace it. Then confirm that the malfunction symptom is eliminated.
STEP 5. Using scan tool MB991958, check actuator test.
1. Turn the ignition switch to the "ON" position.
2. Check the following items in the actuator test. Refer to MFI, Actuator Test Reference Table. Actuator Test Reference Table
a. Item 9: Fuel pump.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the actuator operating properly?
YES : Go to Step 6.
NO : Repair or replace it.Then confirm that the malfunction symptom is eliminated.
STEP 6. Check the ignition system.
1. Connect the timing to terminal No. 1 of the ignition coil connector B-101, B-102, B-121 or B-122 in order.
2. Crank the engine.
- The timing light flashes.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Does the timing light flash?
YES : Go to Step 7.
NO : Refer to MFI, INSPECTION PROCEDURE 32 -Ignition Circuit System. Inspection Procedure 32
STEP 7. Check the ignition timing.
1. Check the ignition timing at cranking.
Standard value: 5° BTDC ± 3°
Q: Is the ignition timing normal?
YES : Go to Step 8.
NO : Check that the crankshaft position sensor and timing belt cover are in the correct position. Then confirm that the malfunction symptom is eliminated.
STEP 8. Check harness connector B-01 or B-03 or B-26 or B-29 at injector for damage.
Q: Is the harness connector in good condition?
YES : Go to Step 9.
NO : Repair or replace it. Refer to general (electrical), Harness Connector Inspection. Then confirm that the malfunction symptom is eliminated.
STEP 9. Check the injector.
1. Disconnect the injector connector B-01, B-03, B-26 and B-29.
2. Measure the resistance between each injector side connector terminal No. 1 and No. 2.
Standard value: 10.5 - 13.5 ohms [at 20 °C (68 °F)]
Q: Is the measured resistance between 10.5 and 13.5 ohms [at 20 °C (68 °F)]?
YES : Go to Step 10.
NO : Repair the injector. Then confirm that the malfunction symptom is eliminated.
STEP 10. Check harness connector B-22 at ECM [M/T] or PCM [A/T] for damage.
Q: Is the harness connector in good condition?
YES : Go to Step 11.
NO : Repair or replace it. Refer to general (electrical), Harness Connector Inspection. Then confirm that the malfunction symptom is eliminated.
STEP 11. Check for harness damage between injector connector and ECM [M/T] or PCM [A/T] connector.
a. Check the harness wire between injector connector B-01 (terminal No. 2) and ECM [M/T] or PCM [A/T] connector B-22 (terminal No. 153) at No. 1 cylinder.
b. Check the harness wire between injector connector B-29 (terminal No. 2) and ECM [M/T] or PCM [A/T] connector B-22 (terminal No. 146) at No. 2 cylinder.
c. Check the harness wire between injector connector B-03 (terminal No. 2) and ECM [M/T] or PCM [A/T] connector B-22 (terminal No. 140) at No. 3 cylinder.
d. Check the harness wire between injector connector B-26 (terminal No. 2) and ECM [M/T] or PCM [A/T] connector B-22 (terminal No. 139) at No. 4 cylinder.
Q: Is the harness wire in good condition?
YES : Check the following items, and repair or replace the defective items.
a. Check the ignition coil and spark plugs.
b. Check if the injectors are clogged.
c. Check if fuel is contaminated.
d. Check compression.
Then confirm that the malfunction symptom is eliminated.
NO : Repair it. Then confirm that the malfunction symptom is eliminated.