Some Toyota Highlander owners report experiencing issues with their A/C unit not getting cold, which can stem from several common problems. These include low or overcharged refrigerant levels that impact cooling efficiency, necessitating a refrigerant recharge. Additionally, a malfunctioning compressor may lead to inadequate cooling, requiring repair or replacement. Some owners find that a clogged cabin air filter restricts airflow, which can be resolved by regular filter replacements. Dirty condenser or evaporator coils can also hinder heat exchange, and cleaning these components may be necessary for improved cooling performance. Furthermore, a dirty or sluggish blower motor can reduce airflow, and its cleaning or replacement can restore functionality. Owners may also encounter problems caused by a bad fuse or relay, which can disrupt A/C operation and may require checking and replacing damaged parts. In rare cases, a fault in the climate control unit itself can prevent cooling, necessitating inspection if all other components are functioning correctly. Regular maintenance is crucial for optimal A/C performance, and owners are advised to seek assistance from qualified technicians if they cannot diagnose or fix the problem themselves.

Some Toyota Highlander owners report experiencing intermittent starting issues, requiring multiple attempts to start the vehicle. Common factors contributing to these problems include a dead or failing battery, which may present symptoms like dim headlights and slow engine cranking. Additionally, some owners encounter alternator problems that prevent the battery from charging properly, leading to starting difficulties. A failed starter can also be a culprit, necessitating several tries to get the vehicle running. Furthermore, issues with electrical components, such as faulty hood or door switches, may contribute to these starting problems. Minor glitches like corrosion or loose connections at the battery terminals can also lead to starting issues. It is recommended that owners systematically check the battery, alternator, starter, electrical components, and battery terminals to effectively diagnose and resolve these intermittent starting concerns.