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Problem Symptoms Table

When the malfunction is not confirmed in the diagnostic trouble code check and the problem still can not be confirmed in the basic inspection, use this table and troubleshoot according to the priority order given below.

PROBLEM SYMPTOMS TABLE - ENGINE CONTROL

Symptom Suspected Area
Engine does not crank (Does not start)
  1. MG1
  2. Hybrid system
  3. Immobilizer
  4. Push start system
No initial combustion (Does not start)
  1. ECM power source circuit
  2. Fuel pump control circuit
  3. Sparkplug
  4. Immobilizer system
  5. Injector
  6. ECM
  7. Crankshaft position sensor circuit
No complete combustion (Does not start)
  1. Fuel pump control circuit
  2. Sparkplug
  3. Immobilizer system
  4. Injector
  5. Crankshaft position sensor circuit
Engine cranks normally but difficult to start
  1. Fuel pump control circuit
  2. Compression
  3. Sparkplug
  4. Injector
  5. Crankshaft position sensor circuit
Difficult to start with cold engine
  1. Fuel pump control circuit
  2. Sparkplug
  3. Injector
  4. Crankshaft position sensor circuit
Difficult to start with hot engine
  1. Fuel pump control circuit
  2. Sparkplug
  3. Injector
  4. Crankshaft position sensor circuit
High engine idle speed (Poor idling)
  1. ECM power source circuit
  2. Electronic throttle control system
Low engine idle speed (Poor idling)
  1. Fuel pump control circuit
  2. Electronic throttle control system
  3. Injector
Rough idling (Poor idling)
  1. Compression
  2. Electronic throttle control system
  3. Injector
  4. Fuel pump control circuit
  5. Sparkplug
Hunting (Poor idling)
  1. ECM power source circuit
  2. Electronic throttle control system
  3. Fuel pump control circuit
Hesitation/Poor acceleration (Poor driveability)
  1. Fuel pump control circuit
  2. Injector
  3. Sparkplug
  4. HV transaxle
Surging (Poor driveability)
  1. Fuel pump control circuit
  2. Sparkplug
  3. Injector
Engine stalls soon after starting
  1. Fuel pump control circuit
  2. Electronic throttle control system
  3. Immobilizer
  4. Crankshaft position sensor circuit
Unable to refuel/Difficult to refuel
  1. ORVR system
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