Auto Idle Stop System Inspection (With Auto Idle Stop System)

NOTE: 

• Before you do this inspection, check for the following conditions. If any of the following condition is found, reset the 12 volt battery sensor.
  • 12 volt battery charge procedure; Check if the 12 volt battery charge is properly done. When the 12 volt battery charge procedure is not correctly followed such as charging the 12 volt battery using a 12 volt battery charger without disconnecting the 12 volt battery terminals, it may cause inaccurate measurement of the 12 volt battery sensor current and cause idle stop malfunction.
  • 12 volt battery negative terminal; When any electric devices or additional earth cables are directly connected to the negative terminal, you need to remove them.
• 12 volt battery sensor reset procedure; Turn the vehicle to the OFF (LOCK) mode, and disconnect the 12 volt battery sensor connector, then reconnect it.

1. Check under these conditions:

• Vacuum in the brake booster is enough.

  NOTE:  At higher altitudes, auto idle stop is often prevented because of the lack of vacuum in the brake booster.

• No indicators are on in the gauge.
• Shift position indicator does not blink.
• Starter system indication is not indicated .
• The 12 volt battery is fully charged .

  NOTE:  If the 12 volt battery is replaced, do the 12 volt battery internal resistance reset procedure .

• Hood is closed.
• All electrical items (headlights, blower fan, radiator fan, rear window defogger, A/C, etc.) are off.
• PCM idle learn procedure is completed .
• Drive the vehicle on a flat road or downhill.
• Idle stop off switch is not on.

  NOTE:  If there is a problem on the idle stop off switch operation, do the following procedure:

  • Test the idle stop off switch .
  • Do the gauge control module self-diagnostic function .
• Snow switch is not on.
• Driver fasten the seat belt (check the seat belt indicator and caution).
• SRS yaw rate-acceleration neutral position memorization is completed .
• ACC system operating state is not changed (kept ON or OFF).

2. Drive the vehicle to warm up the vehicle, and check the following items that meet the temperature requirement :

• ECT SENSOR 1
• ESTIMATED BATTERY TEMPERATURE (BATTERY SENSOR)

  NOTE:  The 12 volt battery temperature is easy to rise when the engine is idling with the hood closed. If the outside air temperature is low condition, the 12 volt battery temperature does not rise enough.

• ATF TEMPERATURE

3. Start the engine, and test-drive the vehicle under these conditions:

• Drive the vehicle at 25 mph (40 km/h), then stop the vehicle within 5-15 seconds.
• Press and hold the brake pedal until the vehicle stops (do not pump the brake pedal or do not brake suddenly).
• Keep the brake pedal pressed after the vehicle stops.

NOTE: 

Do not turn the steering wheel when just before the vehicle stop.

4. Repeat steps 1 through 3 several times, then check the auto idle stop system. If the auto idle stop system works, the system is OK. If the auto idle stop system does not work, do the symptom troubleshooting .