KikoUK

Quick update in case someone else stumbles upon the same problem. I intentionally didn't report back straight after fixing the car as I wanted some time to pass, but after over a thousand miles, there are no issues and the fix was actually really easy once I got my cable and techstream software installed. Once I scanned for errors, the only error present was C1342 - Hydraulic System Malfunction (FL). Cleared the error and car was back to normal straight away and hasn't had any issues since. I'd like to also thank everyone who answered above and tried to help. Safe driving

Update-1: Tried disconnecting the battery, left it off for 10-15 minutes, when I started the vehicle afterwards it stated that it's booting up the system, had to press the start button again in order to actually bring it to the normal "ready" state, but the errors reappeared as soon as I tried to drive. The funny thing is, when I start the car for first time after not driving it for a few hours, the brake pedal feels normal at first, but then as soon as it "realizes" that there are errors, it starts beeping and the pedal gets super firm. I also called my local Lexus dealer and asked how much they would charge me for the job I did myself (new calliper and sliding pins/shoes) and they said that would cost £800 Don't regret doing it myself even after having those errors.. I've ordered Techstream cable/software but it will arrive in almost 10 days. I'll keep you guys updated.

I swapped the brake line from the old to the new calliper in 15 seconds while the brake line was compressed.

I'm just hoping that not using Techstream when bleeding that brake has not damaged my ABS pump module as apparently that's rather expensive and I'll just have to bleed the brakes with Techstream attached to remedy the issue. @Illogan Do you think bleeding the brakes without Techstream can damage the ABS pump?

In a hindsight, I should have, was considering it to be on the safe side. But got mislead by people online saying that you don't need Techstream for bleeding front brakes as apparently only needed when bleeding rear brakes where the battery is. I guess they are wrong

In need of a bit of advice guys. Car is RX450h 2013 - I bled just one of my front brakes as I had to replace a seized caliper and didn't use the Techstream software/procedure. As soon as I started bleeding and turned the car on it said "Brake malfunction", "ABS Malfunction", there is a constant beeping sound when the car is turned on and now the brake pedal is super firm and the car doesn't stop as good as before. I tested the brakes on a long stretch and now when I brake hard, the car kind of steers to the right (I serviced the left brake caliper). Does that mean that there is still air in the brakes? I bled until there was no air bubbles and didn't leave the brake reservoir go under minimum. Do I need to bleed the same brake again with Techstream attached and erase error codes? I guess it's worth mentioning that the vehicle had no errors prior to bleeding the brake. Thank you in advance.