Along with the other Autobots, Ratchet was transformed into a human by at Christmas. He was disgusted with his new human body, mainly due to that he missed his old Autobot one. He later helped Prowl and Optimus rescue a woman out of a burning building. After battling Megatron and his Decepticon army (and watching them vanish without a trace), Optimus concluded that Soundwave had placed the Autobots in a virtual reality program to contain them (and was unknowingly reprogramming them into Decepticons).
After all, in 'Revenge of the Fallen' Ratchet has around 4-5 lines! (You could say 'uh, Jolt had none', but he was a last-minute addition, you can forgive that) At least in the first one they gave him some good moments, but when have you ever seen a full, clear Ratchet transformation sequence?
At some point after arriving in the junkyard, Ratchet was sighted by a human, whom quickly took a picture of him and uploaded it on the internet. He was found by Bumblebee and Raf, whom tried to convince him to join them on their quest to find the other Autobots. However, Ratchet revealed to them that he had felt the war between the Autobots and Decepticons was over, claiming that he and the other Autobots had lost. After Raf expressed his surprise in Ratchet's decision to quit, Ratchet transformed into robot mode and asked him what the Autobots could do without a base of operations or any other resources.
Ratchet would transform into an ambulance (cargo van type) and was colored white with red stripes and emergency lights. Ratchet had two robot modes, though only one was usually seen in the comic run and the television cartoon. Ratchet was one of the original and the longest-lived of all Transformers in the comic series. Often a fan favorite, he was a healer first, but a soldier nonetheless. His courage and loyalty are demonstrated time and again.