[Previous][Next]
Inspection procedure 4: Cranks, won’t start
 
 
 
 
Cranks, Won't Start Circuit
  • Refer to Inspection Procedure 26 - Ignition Circuit System .
 
 
CIRCUIT OPERATION
  • Refer to Inspection Procedure 26 - Ignition Circuit System .
 
 
COMMENT
  • In cases such as the above, the cause is probably no spark, fuel delivery, or fuel quality problems. In addition, foreign materials (water, diesel fuel, etc.) may be mixed with the fuel.
 
 
TROUBLESHOOTING HINTS (The most likely causes for this case:)
  • Battery failed.
  • Fuel pump system failed.
  • Ignition system failed.
  • Injector system failed.
  • Poor compression.
  • Contaminated fuel.
  • Timing chain in out of place.
  • ETACS-ECU (immobilizer) failed <vehicles without KOS>.
  • KOS&OSS-ECU failed <vehicles with KOS>.
  • ECM failed.

 
 
DIAGNOSIS
Required Special Tools:
  • MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
  • MB992745: V.C.I.-Lite main harness A
  • MB992747: V.C.I.-Lite USB cable short
  • MB992748: V.C.I.-Lite USB cable long
  • MB991958: Scan Tool (M.U.T.-III Sub Assembly)
    • MB991824: Vehicles Communication Interface (V.C.I.)
    • MB991827: M.U.T.-III USB Cable
    • MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Using scan tool (M.U.T.-III), read the diagnostic trouble code (DTC).
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).
(1) Connect scan tool (M.U.T.-III). Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) .
(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.
Is any DTC set?
Refer to, Diagnostic Trouble Code Chart .
Go to Step 2.
 
STEP 2. Check the injector.
  • Injector check (Refer to ).
Is the measured resistance normal?
Go to Step 3.
Replace the faulty injector. Then confirm that the malfunction symptom is eliminated.
 
STEP 3. Measure the power supply voltage at injector harness side connector.
(1) Disconnect the injector connector and measure at the harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal power supply line and ground.
  • Voltage should be battery positive voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is battery positive voltage (approximately 12 volts) present?
Go to Step 4.
Repair or replace the connector(s), or check and repair the harness of open circuit and short to ground in power supply line between MFI relay connector and injector connector. Then confirm that the malfunction symptom is eliminated.
 
STEP 4. Check of harness damage in power supply line between MFI relay connector and injector connector.
Are the harness wires in good condition?
Go to Step 5.
Repair the connector(s) or wiring harness. Then confirm that the malfunction symptom is eliminated.
 
STEP 5. Using scan tool (M.U.T.-III), check data list.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following item in the data list. Refer to Data List Reference Table .
  1. Item 1: Power Supply Voltage
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Are they operating properly?
Go to Step 6.
Repair or replace it. Then confirm that the malfunction symptom is eliminated.
 
STEP 6. Using scan tool (M.U.T.-III), check actuator test.
(1) Turn the ignition switch to the "ON" position.
(2) Check the following item in the actuator test. Refer to Actuator Test Reference Table .
  1. Item 9: Fuel pump
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Is the actuator operating properly?
Go to Step 7.
Repair or replace it. Then confirm that the malfunction symptom is eliminated.
 
STEP 7. Check the ignition system.
(1) Connect the timing light to terminal power supply line of the ignition coil connectors in order.
(2) Crank the engine.
  • The timing light flashes.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Does the timing light flash?
Go to Step 8.
Refer to Inspection Procedure 26 - Ignition Circuit System .
 
STEP 8. Check the spark plugs.
Refer to GROUP 16, Ignition System - On-vehicle Service - Spark Plug Check and Cleaning .
Are there any abnormalities?
Replace the spark plug. Then confirm that the malfunction symptom is eliminated.
Go to Step 9.
 
STEP 9. Check the ignition coil.
Refer to GROUP 16, Ignition System - On-vehicle Service - Ignition Coil Check .
Are there any abnormalities?
Replace the ignition coil. Then confirm that the malfunction symptom is eliminated.
Go to Step 10.
 
STEP 10. Check the compression pressure.
Refer to GROUP 11A, On-vehicle Service - Compression Pressure Check .
Is the compression pressure normal?
Go to Step 11.
Repair it. Then confirm that the malfunction symptom is eliminated.
 
STEP 11. Check the ignition timing.
Refer to GROUP 11A, On-vehicle Service - Ignition Timing Check .
Is the ignition timing normal?
  • Check the following items, and repair or replace the defective items.
    1. Check if the injectors are clogged.
    2. Check if fuel is contaminated.
  • Then confirm that the malfunction symptom is eliminated.
Check for installed conditions of the timing chain. Then confirm that the malfunction symptom is eliminated.