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Symptom Troubleshooting Index

When the vehicle has one of these symptoms, check for a diagnostic trouble code (DTC) with the HDS. If there is no DTC, do the diagnostic procedure for the symptom, in the sequence listed, until you find the cause.

SYMPTOM TROUBLESHOOTING CHART

Symptom Diagnostic procedure Also check for
Engine will not start (MIL works OK, no DTCs set)
  1. Test the battery (see BATTERY TEST ).
  2. Test the starter (see STARTER PERFORMANCE TEST ).
  3. Check the fuel pressure (see FUEL PRESSURE TEST ).
  4. J32A3 engine: Troubleshoot the fuel pump circuit (see FUEL PUMP CIRCUIT TROUBLESHOOTING ).
  • Low compression
  • No ignition spark
  • Intake air leaks
  • Locked up engine
  • Jumped timing belt
  • Contaminated fuel
Engine will not start (MIL comes on and stays on, or never comes on at all, no DTCs set) Troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING (PART 2) ).  
MIL comes on and stays on, or never comes on at all, no DTCs set Troubleshoot the MIL circuit (see MIL CIRCUIT TROUBLESHOOTING ).  
Engine will not start (immobilizer indicator stays on or flashes) Check the immobilizer system.  
Engine starts but stalls immediately (MIL works OK, no DTCs set, immobilizer indicator stays on or flashes) Check the immobilizer system.  
Engine is hard to start (MIL works OK, no DTCs set)
  1. Test the battery (see BATTERY TEST ).
  2. Check the fuel pressure (see FUEL PRESSURE TEST ).
  3. Clean the throttle body (see THROTTLE BODY CLEANING ).
  • Low compression
  • Intake air leaks
  • Contaminated fuel
  • Weak spark
Cold fast idle too low (MIL works OK, no DTCs set)
  1. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  2. Check the idle speed (see IDLE SPEED INSPECTION ).
  3. Clean the throttle body (see THROTTLE BODY CLEANING ).
  
Cold fast idle too high (MIL works OK, no DTCs set)
  1. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  2. Check the idle speed (see IDLE SPEED INSPECTION ).
  3. Adjust the throttle cable (see THROTTLE CABLE ADJUSTMENT ).
  4. Do the throttle position learning check (see THROTTLE POSITION LEARNING CHECK ).
  
Idle speed fluctuates (MIL works OK, no DTCs set)
  1. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  2. Check the idle speed (see IDLE SPEED INSPECTION ).
  3. Adjust the throttle cable (see THROTTLE CABLE ADJUSTMENT ).
  4. Do the carbon accumulation check (see CARBON ACCUMULATION CHECK ).
  5. Troubleshoot the A/C signal circuit (see A/C SIGNAL CIRCUIT TROUBLESHOOTING ).
 Intake vacuum leaks
After warming up, idle speed is below specification without load (MIL works OK, no DTCs set)
  1. Troubleshoot the alternator FR signal circuit (see ALTERNATOR FR SIGNAL CIRCUIT TROUBLESHOOTING ).
  2. Do the carbon accumulation check (see CARBON ACCUMULATION CHECK ).
  
After warming up, idle speed is above specification without load (MIL works OK, no DTCs set)
  1. Adjust the throttle cable (see THROTTLE CABLE ADJUSTMENT ).
  2. Troubleshoot the alternator FR signal circuit (see ALTERNATOR FR SIGNAL CIRCUIT TROUBLESHOOTING ).
  3. Troubleshoot the PSP switch signal circuit (see PSP SWITCH SIGNAL CIRCUIT TROUBLESHOOTING ).
  4. Inspect the APP sensor signal (see APP SENSOR SIGNAL INSPECTION ).
  
After warming up, idle speed drops when steering wheel is turning (MIL works OK, no DTCs set)
  1. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  2. Troubleshoot the PSP switch signal circuit (see PSP SWITCH SIGNAL CIRCUIT TROUBLESHOOTING ).
  3. Do the carbon accumulation check (see CARBON ACCUMULATION CHECK ).
 Power steering system problems
Low power (MIL works OK, no DTCs set)
  1. Check the fuel pressure (see FUEL PRESSURE TEST ).
  2. Adjust the throttle cable (see THROTTLE CABLE ADJUSTMENT ).
  • Low compression
  • Incorrect camshaft timing
  • Incorrect engine oil level
Engine stalls (MIL works OK, no DTCs set)
  1. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  2. Check the fuel pressure (see FUEL PRESSURE TEST ).
  3. Check the idle speed (see IDLE SPEED INSPECTION ).
  4. Troubleshoot the brake pedal position switch signal circuit (see BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING ).
  • Intake air leaks
  • Faulty harness and sensor connections
  • Fuel contamination
Difficult to refuel (MIL works OK, no DTCs set)
  1. Check the fuel vent tube between the EVAP canister and the fuel tank.
  2. Check the fuel tank vapor recirculation tube between the fuel pipe and the fuel tank.
  3. Replace the fuel tank (see FUEL TANK REPLACEMENT ).
  • Malfunctioning gas station filling nozzle.
  • Filler neck restriction
Fuel overflows during refueling (No DTCs set) Replace the fuel tank (see FUEL TANK REPLACEMENT ). Malfunctioning gas station filling nozzle.
Fuel cap warning message comes on and stays on (MIL works OK, no DTCs set) Troubleshoot the fuel cap warning message system (see FUEL CAP WARNING MESSAGE SYSTEM TROUBLESHOOTING ).  
HDS does not communicate with the ECM/PCM or the vehicle Troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING (PART 2) ).  
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