There are 2 owner-reported brakes complaints for the 2005 Lexus ISin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
As I prepared to make a right turn onto a busy street, I suddenly could not brake normally. Instead, I was unable to press the brake down as a balloon like feeling pushed it back up, but it also did not return all the way up to its normal position. The result was I was moving with no way to slow down the car. Fortunately, I was not moving at a high speed and immediately shifted into park. I was fortunate this did not occur while I was at full speed. The brake lights did turn on at the time of the issue. An independent mechanic suspects a brake booster failure. Just a month before, another mechanic performed routine maintenance and found no signs of this issue. Just 6 months before, I purchased the vehicle used with no mention of this sort of past issue.
LEXUS IS300 2005 BRAKE MALFUNCTION. *BF WHEN THE CONSUME ATTEMPTED TO APPLY THE BRAKES, THE VEHICLE WOULD NOT STOP, WHICH RESULTED IN THE CONSUMER HITTING A PARKED VEHICLE. THE CONSUMER BELIEVED THE BRAKE BOOSTER FAILED. *JB
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 25, 2026