Tijuana can be avoided completely, going South at the border there is a right hand turn and then a left tun that leads to the customs check point, stay on the right hand lane once past the customs area there is another left turn, there is an exit to the right that goes over the Tia Juana river and leads you down to the other side, stay on this road, it will go up a hill next to the border fence.
Once the road reaches the crest, the road turns left and goes down, be careful sharp curves, at the bottom stay on the right lane and exit, this merges with the road to Playas de Tijuana, now stay on the center lane up a hill, left curve down hill, up another hill and then you come to the "Y" left lanes go to Rosarito and Ensenada toll road and right lane(s) to Playas, now you are on the toll road to Rosarito and Ensenada.
On the way back, stay on the same road do not make any turns, once past most of the town the street becomes a one way, stay on the second lane from the left, this leads straight to the over pass to the border, go slow lots of traffic and idiots behind the steering wheel.
if you need to visit the Banjercito modules, Tijuana is not easy to get to them, specially with big rigs, I definitely recommend Tecate for that.
Buen viaje
navegator