Toyota Highlander Stop Start Not Working

The Toyota Highlander (also called the Toyota Kluger in other regions) Engine Control Unit (ECU) monitors a number of inputs to determine when the engine should be turned off (auto stop).

Due to the specific requirements for auto stop to initiate, it often appears that the start stop system is not working, but it’s often due to one or more of the conditions that have not been met. In this situation, you may see the stop start unavailable warning light along with a message.

Toyota Highlander Stop Start Messages

Along with the auto start stop unavailable warning light, the following messages may display:

‘Press brake more to activate’

This means that the brake pedal has not been sufficiently depressed. Apply greater pressure on the brake pedal and the stop start system will operate.

‘Non-Dedicated Battery’

A battery has been installed that is not designed for use with a stop start system.

‘Battery Charging’

This means that the battery charge may be low and auto stop will be temporarily prohibited to prioritize charging of the battery. After the engine runs for a certain amount of time, the auto stop start system will be enabled. If the warning light and message is displayed continuously for more than an hour, the battery may be deteriorated.

‘In Preparation’

The vehicle is being driven in a high altitude area, or the brake booster vacuum is low. This can also occur if the brake pedal has been depressed further or pumped. When the brake booster vacuum reaches a predetermined level, the auto stop start system will be enabled.

‘For Climate Control’

The air conditioning system is being used when the ambient temperature is either too high or too low. When the difference between the set temperature and cabin temperature becomes small, the auto stop start system will be enabled. The warning light and message also displays when the windshield defogger is on.

Toyota Highlander Stop & Start System

The Toyota Highlander stop start system will automatically stop the engine if the following conditions have been met:

• The hood properly closed.
• The driver’s seat belt is fastened.
• The driver’s door is closed.
• The brake pedal is being firmly pressed.
• The D shift position is selected.
• The vehicle has been driven a certain amount of time.
• The mode mode is set to either ‘Normal’ or ‘ECO’ and is not in ‘Snow’ mode.
• The windshield defogger is switched off.
• The engine has sufficiently warmed up.
• The accelerator pedal is not being pressed.
• The outside temperature is 23°F (-5°C ) or higher.

Toyota Highlander Stop & Start System Unavailable

The Toyota Highlander ‘Stop & Start System Unavailable‘ warning message may appear along with the warning light, resulting in the engine not being stopped if the following conditions occur:

• When the air conditioning system is being used.
• When the battery is undergoing a periodic recharge.
  
• When the battery fluid temperature is extremely low or high.
• Stop and start may not operate for a while after the battery terminals have been disconnected and reconnected.
• Battery voltage greater than 12 V. If the battery is not sufficiently charged, for example,
  • if the vehicle has been parked for a long time and the battery charge has decreased. Battery state of charge in the ECM is greater than 75%
  • the electric load is large
  • the battery fluid temperature is excessively low
  • the battery has deteriorated.
    
• When the brake booster vacuum is too low. The brake booster vacuum must be greater than 45 kPa (7 PSI).
  
• When the elapsed time since the engine was restarted is short.
  
• When the vehicle is stopped frequently, such as when in a traffic jam.
  
• Ambient and engine coolant temperature correlation must meet specified values.
• Ambient and transmission fluid temperature correlation must meet specified values.
  
• When the vehicle is stopped on a steep incline.
  
• When the steering wheel is being operated.
  
• When the vehicle is being driven in a high altitude area.