I was going to mention a horde of 1960s/1970s police dramas. And Emergency. But I’ve been partly ninja’d.
Highway Patrol (both iterations), Dragnet the TV series and the movie, Adam-12, CHiPs, Starsky and Hutch. I’m sure there are more.
A lot of liberties were taken with locations though. As mentioned above, the stationhouse for Emergency’s fictional Squad 51 is real. As was Rampart Hospital. There really is a Rampart district in LA. But they were 30+ miles apart, and the shots of most of the generic suburbia calls were another 20-ish miles away in the opposite direction. But conveniently near the studio. Of course when the script needs a beach or harbor or mountain scene to establish the SoCal locale they drive the extra 20 or 40 miles it takes to get there. Then haul the patient back to good 'ol Rampart.
Adam-12 was another one famous for Malloy and Reed jumping clear across LA at the drop of a patrolman’s spiffy hat. It’s a big city; a really big city. 500 square miles worth, plus the areas outside city proper that LAPD is contracted to serve.
Dragnet’s Parker Center really was LAPD headquarters at the time. It’s now an abandoned asbestos-infested superfund site of a building with homeless camping in the shadows. The new and much larger HQ is a couple blocks away.
Watching these shows, even going back to the original Highway Patrol of the 1950s, is an amazing time capsule of LA and environs’ visual history.
Moving north, The Streets of San Francisco was filmed there; that’s one town that’s hard to fake. Likewise the entire Dirty Harry franchise.
I’ve told this story of almost the right place a time or two. In the 70’s there was a TV drama about students in a prestigious law school:
Although the story was modeled on super prestigious super competitive programs like Harvard, the actual location of the school was always ambiguous.
All the exterior campus scenes were shot at USC in downtown Los Angeles. Which I was attending at the time. The campus main admin building had been one of the earliest truly huge imposing masonry structures there, had lots of ivy growing on it, and totally looked the part of a long-standing prestigious law school. So of course, that’s what the series used. Lots of canned shots of students entering, standing in the foyer, etc.
The actual USC law school (also pretty prestigious and competitive, at least as to the West Coast) was an ugly late 1960s bare cast concrete Brutalist monstrosity diagonally opposite the main admin building and down a bit.
So whenever we saw one of those exterior establishing shots we’d always shout at the TV: “No, stupid! Turn the camera around; the law school is right behind you!” They never listened. 
Growing up in LA you see a lot of stuff you recognize, either specifically or just stylistically. Good times.