Inspection Procedure 3
Engine Cranks, but does not Start.TECHNICAL DESCRIPTION
If the engine cranks, but does not start, an MFI system problem may exist in addition to a malfunctioning immobilizer system. The engine will not start if the ignition key has not been properly registered.
TROUBLESHOOTING HINTS
- Malfunction of MFI system
- Malfunction of immobilizer-ECU
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991911: M.U.T.-III Main Harness B
STEP 1. Check the battery voltage.
Measure the battery voltage during cranking.
Q: Is the voltage 8 volts or more?
YES: Go to Step 2.
NO: Check the condition of the battery. Refer to Battery Check.
STEP 2. Using scan tool MB991958, read the MFI system diagnostic trouble code.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to "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 "ON" position.
3. Read the diagnosis code.
Q: Have any DTCs set?
Yes: Go to Step 3
No: Go to Step 5.
STEP 3. Using scan tool MB991958, read the diagnostic trouble code.
Q: Have any immobilizer system DTCs set?
YES: Refer to Battery Check.
NO : Go to Step 4.
STEP 4. Check for MFI system DTCs.
Q: Have any MFI system DTCs set?
YES : Refer to MFI Diagnosis in Computer and Control Systems.
NO : Go to Step 5.
STEP 5. Attempt to start the engine.
Q: Does the engine start?
YES : The procedure is complete (If no malfunctions are found in all steps, an intermittent malfunction is suspected. Refer to How to Use Troubleshooting/Inspection Service Points -How to Cope with Intermittent Malfunction).
NO : Refer to MFI Diagnosis - Symptom Chart in Computer and Control Systems. If the malfunction is not resolved, replace the immobilizer-ECU. Then register the password (secret code) and encrypted code. The engine should now start.