2006 Lexus RX 400h showing check hybrid system and not starting

[Ashit]

56 reg Lexus rx400h Battery was flat and jump started it and went for a long ride(30mins). Whilst driving message came check cvs system and check hybrid system. Car was driving fine. Came home switched off the car and then tried to switch on but wouldn’t . Message comes check hybrid system. All other dashboard lights come on. Any suggestions . Thanks in advance.

[Herbie]

Most likely the 12V Battery going bad. Either give it a proper charge overnight or replace it and I reckon that'll solve your problem.

If you have a multimeter it might be a good idea to check the Battery standing voltage and compare it against the chart below. If you can get the car into the READY state then you should be able to measure about 14.5V across the Battery as the system attempts to charge it.