Inspection Procedure 4
INSPECTION PROCEDURE 4: Cranks, Won't Start
Cranks, Won't Start Circuit
- Refer to INSPECTION PROCEDURE 24 - Ignition Circuit System Inspection Procedure 26.
CIRCUIT OPERATION
- Refer to INSPECTION PROCEDURE 24 - Ignition Circuit System Inspection Procedure 26.
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 immobilizer system.
- Malfunction of the fuel pump system.
- Malfunction of the ignition system.
- Malfunction of the injector system.
- Poor compression
- Contaminated fuel.
- Malfunction of the ECM.
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. 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 after cranking the engine for at least 2 sec.
(3)Read the DTC.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
Q. Is DTC set?
YES Refer to Diagnostic Trouble Code Chart Multiport Fuel Injection (MFI).
NO Go to Step 2.
STEP 2. Check harness connector A-24X at injector relay for damage.
Q. Is the connector in good condition?
YES Go to Step 3.
NO Repair or replace it. Harness Connector Inspection.
Then confirm that the malfunction symptom is eliminated.
STEP 3. Check the injector relay.
(1)Remove the injector relay.
(2)Check for continuity between the injector relay terminals No. 1 and No. 2.
- There should be continuity.
(3)Use jumper wires to connect injector relay terminal No. 1 to the positive battery terminal and terminal No. 2 to the negative battery terminal.
(4)Check for continuity between the injector relay terminals No. 3 and No. 4 while connecting and disconnecting the jumper wire at the negative battery terminal.
- Should be less than 2 ohms. (Negative battery terminal connected)
- Should be open loop. (Negative battery terminal disconnected)
(5)Install
the MFI relay.
Q. Is the measured resistance within the specified range?
YES Go to Step 4.
NO Replace the injector relay. Then confirm that the malfunction symptom is eliminated.
STEP 4. Measure the power supply voltage at injector relay harness side connector A-24X.
(1)Disconnect the connector A-24X and measure at the harness side.
(2)Measure the voltage between terminal No. 4 and ground.
- Voltage should measure battery positive voltage.
Q. Is battery positive voltage (approximately 12 volts) present?
YES Go to Step 5.
NO Repair harness wire between MFI relay connector A-33X (terminal No. 2) and injector relay connector A-24X (terminal No. 4) because of open circuit or harness damage. Then confirm that the malfunction symptom is eliminated.
STEP 5. Measure the power supply voltage at injector relay harness side connector A-24X.
(1)Disconnect the connector A-24X and measure at the harness side.
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between terminal No. 1 and ground.
- Voltage should be battery positive voltage.
(4)Turn
the ignition switch to the "LOCK" (OFF) position.
Q. Is battery positive voltage (approximately 12 volts) present?
YES Go to Step 6.
NO Repair harness wire between ETACS-ECU connector C-304 (terminal No. 10) and injector relay connector A-24X (terminal No. 1) because of open circuit or harness damage. Then confirm that the malfunction symptom is eliminated.
STEP 6. Check for continuity at injector relay harness side connector A-24X.
(1)Disconnect the connector A-24X and measure at the harness side.
(2)Check for the continuity between terminal No. 2 and ground.
- Should be less than 2 ohms.
Q. Does continuity exist?
YES Go to Step 7.
NO Repair harness wire between injector relay connector A-24X (terminal No. 2) and ground because of open circuit or harness damage. Then confirm that the malfunction symptom is eliminated.
STEP 7. Using scan tool MB991958, check data list.
(1)Turn the ignition switch to the "ON" position.
(2)Check the following items in the data list. Refer to Data List Reference Table Data List Reference Table.
1. Item 1: Power Supply Voltage (at cranking).
(3)Turn the ignition switch to the "LOCK" (OFF) position.
Q. Are they operating properly?
YES Go to Step 8.
NO Repair or replace it. Then confirm that the malfunction symptom is eliminated.
STEP 8. 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 Actuator Test Reference Table Actuator Test Reference Table.
2. Item 9: Fuel pump.
(3)Turn the ignition switch to the "LOCK" (OFF) position.
Q. Is the actuator operating properly?
YES Go to Step 9.
NO Repair or replace it. Then confirm that the malfunction symptom is eliminated.
STEP 9. Check the fuel pressure.
Refer to On-vehicle Service - Fuel Pressure Test Testing and Inspection.
Q. Is the fuel pressure normal?
YES Go to Step 10.
NO
Check the following items, and repair or replace the defective items.
- Insufficient fuel pump discharge.
- Fuel pump filter clogged.
STEP 10. Check the left bank injector resistance.
(1)Disconnect the left bank injector connector B-115, B-116, B-120.
(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 11.
NO Replace the faulty injector. Then confirm that the malfunction symptom is eliminated.
STEP 11. Check the right bank injector resistance at intermediate connector B-21.
(1)Disconnect the intermediate connector B-21.
(2)Measure the resistance between each male connector side terminal.
3. Measure the resistance between terminal No. 6 and No. 7 at No. 1 cylinder injector.
4. Measure the resistance between terminal No. 6 and No. 8 at No. 3 cylinder injector.
5. Measure the resistance between terminal No. 6 and No. 9 at No. 5 cylinder injector.
- Resistance should be between 10.5 and 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 14.
NO Go to Step 12.
STEP 12. Check the right bank injector resistance.
(1)Remove the intake manifold.
(2)Disconnect the right bank injector connector, which deviates from the standard value at Step 11.
(3)Measure the resistance between 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 13.
NO Replace the injector. Then confirm that the malfunction symptom is eliminated.
STEP 13. Check harness connector B-101, B-103, B-104 at right bank injector for damage.
(1) Check the injector connector, which deviates from the standard value at Step 11.
Q. Is the harness connector in good condition?
YES Repair harness wire between injector intermediate connector and right bank injector connector because of harness damage. Then confirm that the malfunction symptom is eliminated.
NO Repair or replace it. Harness Connector Inspection.
Then confirm that the malfunction symptom is eliminated.
STEP 14. Check harness connector B-21 at intermediate connector for damage.
Q. Is the harness connector in good condition?
YES Go to Step 15.
NO Repair or replace it. Harness Connector Inspection.
Then confirm that the malfunction symptom is eliminated.
STEP 15. Check harness connector B-10 at ECM and harness connector B-115, B-116, B-120 at left bank injector for damage.
Q. Is the harness connector in good condition?
YES Go to Step 16.
NO Repair or replace it. Harness Connector Inspection.
Then confirm that the malfunction symptom is eliminated.
STEP 16. Check for harness damage between injector connector and ECM connector.
(1)Disconnect the injector connector and ECM connector.
(2)Measure the resistance between injector connector and ECM connector.
6. Injector connector B-101 (terminal No. 2) and ECM connector B-10 (terminal No. 2) at No. 1 cylinder injector.
7. Injector connector B-120 (terminal No. 2) and ECM connector B-10 (terminal No. 3) at No. 2 cylinder injector.
8. Injector connector B-103 (terminal No. 2) and ECM connector B-10 (terminal No. 18) at No. 3 cylinder injector.
9. Injector connector B-116 (terminal No. 2) and ECM connector B-10 (terminal No. 19) at No. 4 cylinder injector.
10. Injector connector B-104 (terminal No. 2) and ECM connector B-10 (terminal No. 50) at No. 5 cylinder injector.
11. Injector connector B-115 (terminal No. 2) and ECM connector B-10 (terminal No. 51) at No. 6 cylinder injector.
- Should be less than 2 ohms.
Q. Is the measured resistance less than 2 ohms?
YES Go to Step 17.
NO Repair it. Then confirm that the malfunction symptom is eliminated.
STEP 17. Check the ignition system.
(1)Connect the timing light to terminal No. 1 of the ignition coil connector B-01, B-04, B-05, B-15, B-18 or B-19 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 18.
NO Refer to INSPECTION PROCEDURE 24 - Ignition Circuit System Inspection Procedure 26.
STEP 18. Check the spark plugs.
Procedures.
Q. Are there any abnormalities?
YES Replace the spark plug. Then confirm that the malfunction symptom is eliminated.
NO Go to Step 19.
STEP 19. Check the ignition coil.
(1)Remove the intake manifold.
(2) Testing and Inspection.
Q. Are there any abnormalities?
YES Replace the ignition coil. Then confirm that the malfunction symptom is eliminated.
NO Go to Step 20.
STEP 20. Check the compression pressure.
Testing and Inspection.
Q. Is the compression pressure normal?
YES Go to Step 21.
NO Repair it. Then confirm that the malfunction symptom is eliminated.
STEP 21. Check the ignition timing.
(1)Check the ignition timing at cranking.
Standard value: 5° BTDC ± 3°
Q. Is the ignition timing normal?
YES
Check the following items, and repair or replace the defective items.
12. Check if the injectors are clogged.
13. Check if fuel is contaminated.
Then
confirm that the malfunction symptom is eliminated.
NO Check for installed conditions of the timing belt. Then confirm that the malfunction symptom is eliminated.