All California emergency vehicles have to have a steady burn solid red light to the front. LAPD uses 1 of the LED pods in their roof light bar for this. Police cars in this series do not have such a light, while the in-car lights for the unmarked vehicles are correct (one red steady burn, one blue blinking).
For a police procedural with supposed military veterans there are a lot of serious firearms handling mistakes. For example in 3/3 the head of the SOG team is repeatedly pointing muzzle of a loaded p226 at a team member after the desert sniper rifle practice. He also puts his hand in front of the barrel after racking the 226. The lead actor makes only a few mistakes but the other actors make a lot of basic firearms mistakes.
"Meet you in 30 minutes." This phrase is constantly being used by Bosch and other police in series. You can't get anywhere in LA in 30 minutes, much less from Hollywood to Santa Monica in "30".