Lexus IS300h Common Problems

Are you familiar with Lexus IS300h common problems?

One of the more attractive sports executive sedans in the segment is the Lexus IS. A small modification was made to the third-generation Lexus IS in 2017, and then a significant update was made in 2020.

The IS competes against the Alfa Romeo Giulia, BMW 3 Series, Audi A4, Jaguar XE, and the upcoming Mercedes-Benz C-Class in a segment that is on the decline. This is partly as a result of the growing popularity of crossovers).

The revised Lexus IS300h still uses the same 2.5-liter inline-4 engine and electric motor setup as the outgoing model. Power is delivered to the rear wheels with the help of a continuously variable transmission.

The most recent IS300h has less horsepower than the previous model. Compared to the previous generation, the total system output is 219 horsepower. Thankfully, the century sprint time of 8.5 seconds has not changed [1].

Additionally, the vehicle’s fuel economy has decreased from 20.4 km/L to 18.5 km/L. Since a decrease in power typically results in greater fuel savings, the vehicle was expected to get better.

The IS is a well-built vehicle with relatively few significant recorded issues. Trouble with the engine, engine electrics, and non-engine electrics have been mentioned by several owners.

Troublesome components include the sat-nav, air-con, and infotainment systems. Fortunately, most of these issues were resolved under warranty.

Most Common Lexus IS300h Problems


  1. Navigation System Issues

There have been several complaints concerning the sat-nav of the Lexus IS300h. One owner complained that the sat-nav went blank [3].

No maps, navigation, or destination options were available. Radio, climate, and phone screens all functioned as expected, but nothing related to navigation was there, not even in the speedometer cluster.

Another complaint was filed regarding the 2013 Lexus IS300H, which had 142000 miles on the odometer [4]. When the owner turned the ignition on, the navigation screen became stuck at the start-up screen, which features the Lexus logo, and would not advance.

The owner attempted every remedy conceivable but in vain. When they pressed the volume button deeply, the stereo turned back on. However, the Lexus logo appeared once more on the navigation screen but did not proceed.

The fuse boxes within the automobile and in the engine bay were all examined and found to be in good condition. The driver removed the stereo, unplugged everything, and then plugged back everything, but the sat-nav was still inoperative.

In a Technical Service Information Bulletin released in 2016 [5], Lexus provided a navigation system rest procedure which included the following steps:

  1. Verify that the navigation system restarts when the ignition is turned on.
  2. Disconnect the vehicle’s 12-volt battery’s negative terminal.
  • Wait for 30 seconds.
  1. Reconnect the vehicle’s 12-volt battery’s negative terminal.
  2. After the multimedia system reloads, check its functionality. The following may happen to the system;
  • After a battery disconnect, it may take up to five minutes to reload.
  • If the navigation system starts operating regularly, go to step 7.
  • This TSB does not apply if the navigation system keeps rebooting; instead, diagnosed according to the Repair Manual.
  1. Initialize the systems of the car as necessary.
  • Refer to the relevant model and model year Repair Manual in the Technical Information System (TIS).
  • Verify that all systems are operating properly.
  1. Air Conditioning Issues

There have several complaints concerning the air-con system of the IS300h. An owner of a 2014 IS300h complained that while in Eco Mode, the air-con light came on but there was no cold air coming from the vents.

Another driver complained that heat came out of the air-con system. The car brought out loud noises from the compressor, noises of gas trying to flow inside the car.

The problem stopped when the driver turned the air-con and the vehicle off, and started it after 5 minutes [7].  The most frequent causes of an inoperable Lexus IS300h air conditioner are refrigerant leaks, electrical climate control problems, or issues with the air conditioning compressor [8].

Most of the time, if the air blowing out of your IS300h isn’t cold enough, there isn’t enough refrigerant in the system.

If it turns out to be a coolant problem, it is advised to have a professional recharge your air conditioner and repair the leak. It can do some damage to the system if you add too much coolant.

  1. Infotainment System Issues

Another major problem with the IS300h concerns the Infotainment System. A 2013 Lexus IS300h owner reported that the entire infotainment system had entered a “boot loop” [9].

The driver argued that downloads are never fully finished by the system. Instead, it kept restarting. The motorist checked at a Toyota dealership nearby, and they suggested replacing the radio, which would cost 994 Euros.

According to Lexus, the data thought to be the cause of the issue was repaired. And the solution calls for a hard reset and the removal of the incorrect data from the system.

The over-the-air update was done, although different vehicles received the software at various times [10]. If you drive a 2014–2016 Lexus IS300h, it is possible that your infotainment system mysteriously crashed.

 It turns out that Lexus released a faulty over-the-air software update that rendered many of its vehicles’ information, navigation, and entertainment systems inoperable.

Unfortunately, you can’t repair the problem yourself. You must take it to a Lexus dealer.

Driving the vehicles is secure. Lexus car owners who encounter these problems should go to their dealer for a system reset. This cannot be done by the corporation with an over-the-air update. You won’t be able to use the GPS, Bluetooth phone calls, or radio until you can reach a dealership.

  1. Engine Idling or Misfiring

The engine of the Lexus IS300h has also caused a problem with the model. First, the car has been reported to not respond to acceleration. The issue was successfully fixed by replacing the throttle body.

However, the major complaint is that the car continued to idle and misfired when idling. A driver argued that the problem happens intermittently and when the car is stopped or functioning at very low revs.

The owner tried several repairs but the issue couldn’t be fixed [11].

A malfunction with either the throttle body or MAF (Mass Air Flow) sensor will be the root of any engine misfiring and poor idling issues you may be experiencing.

These may fill up with carbon and cause the aforementioned issues. In addition, when you try to speed, this may lead to a lack of power. The MAF sensor can be taken out and cleaned with a MAF sensor cleaner.

The best course of action is to clean the throttle body simultaneously using a toothbrush and some throttle body cleaning. Your issue ought to be solved after they are both wiped up.

  1. Heavy Clutch Wear

The IS300h is renowned for its robust clutch. One owner expressed frustration at how heavy the clutch pedal was. The transmission worked smoothly, but it was difficult to press it down [12].

Try changing the transmission fluid if you have this issue. Although the transmission fluid occasionally needs to be changed, it is frequently disregarded in manuals.

It is unlikely to make an impact, though. Most likely, when you try to disengage, the clutch is not disengaging properly, which puts strain on the gears and synchros.

If it’s a hydraulic clutch, it can be that the seals are beginning to let a little air into the system or that the pressure plate springs aren’t functioning properly.

Additionally, the clutch is about to fail if you notice that the biting point is unusually high. To solve the issue, a replacement clutch must be installed.

Read Also: Lexus NX 300h Problems


Just like any other car, the Lexus IS300h is not faultless. There have been several complaints about the infotainment system’s graphics, which are woefully out of date.

Users have decried its mouse-style controller, which is difficult to use, the sub-menus, and the lack of a postcode input for the sat-nav.

Additionally, complaints have been made concerning the hybrid powertrain having a weight penalty but offering no discernible mpg advantages over diesel. The engine and clutch have also been an issue with the Lexus IS300h model.

Finding out what’s wrong with your Lexus IS300h or simply knowing what to watch out for in the future should be made easier by being aware of these typical Lexus IS300h issues.

Whenever an issue that is beyond your knowledge arises, take the car to a professional for repair.

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