This page of the guide has a walkthrough for the second part of chapter 5 of Uncharted 2: Among Thieves called Urban Warfare. Nathan Drake continues eliminating enemies encountered in the city. The hero will also have to climb the signs and other elements of the environment.
Throwing a grenade reveals your position. Note that one of the opponents will hide at the top. Shoot him first and go to that place (use the ladder presented in the right photo). When you are at the top, you will have a much better position to fight the enemies. However, remember that the opponents will be able to approach you from behind by using the same ladder. In addition, one of the enemies will have a shield - kill him with a grenade.
When everyone is dead, go down and follow the road. Watch a short cut-scene during which enemies will attack you from inside a car (one of them will use a heavy machine gun). You don't have to kill them, but just hold on for a few seconds. It's not difficult - hide behind a cover and throw a few grenades in their direction.
If all goes according to your plan, a new partner will appear in the area, rescuing you with a rocket launcher.
Now it's time for a bit of platforming elements. Follow the woman to closed doors - you need to open them. To do this, go back to the place where the fight took place (go near the exploded car) and look for a street light. Climb the signs, jump on the wooden roof, and then towards the next building. Climb the protruding bricks...
...to get inside another building. Stand on the dilapidated floor and jump to its other part. You reach a place with wooden beams. By sticking to them, you will be able to jump to subsequent bricks on the wall. After that, you will get back on the destroyed floor on the opposite side of the building. Climb the drawer and head to the neighboring buildings (you will also walk on another beam).
While you are on the roof, go to its edge jump to the partially destroyed balcony. Then make your way to the sign nearby. While you are holding to it, you will hear the upcoming opponents. It depends on you whether you kill them from that position or jump to the ground. Know, however, that these enemies will try to break through the door and attack your partner (don't worry, she is completely safe). If you attack them before they do that, you will have to open this door yourself.
Regroup with Chloe and get ready for another fight - the hostiles near the door aren't alone. The rest of the opponents is a little farther away and some of them are on the balconies. If you go towards the stairs, you will find a small ammunition storage room on the left. Be sure to check that place.
The stairs are at the end of the dead end. Boost your partner and then use the ladder to get into the building.
You are in a kitchen - destroy three boards to move on. In the next room, go to the ruined walkway and lift up the beams to unlock the passage.
Go outside to complete the chapter.