A 32-year-old Jeep no scan tool can read: Claude Code and Codex decoded its engine computer and ran the fuel pump

"Claude reverse engineered my 32-year-old Jeep. Then it started controlling it." Muhammad Zulali's video post drew about 3,300 likes on Nov. 10. His 1994 Jeep Cherokee has no OBD2 port and no scan tool that works on it.

According to the video description, he wired a $3 Arduino to the engine computer and had Claude Code and Codex figure it out. Over about a week they read the computer live, logged drives, copied its entire program and ran their own code inside it. Chapters include "Claude runs the fuel pump" and "Codex runs code inside the computer." Wiring, code and agent instructions are in the GitHub repo xj-scanner.

It started with a failed smog test over NOx, and the video ends on smog day. When a reply suggested tuning, he said there were many hidden dealer and factory controls but he left them alone for the test "since that's legally questionable."

He invites owners of 1991 to 1995 Jeeps and Chryslers to clone the repo and let a coding agent walk them through the hookup, adding that he is not a mechanic and some engine explanations may be wrong. One commenter asked whether Codex only wrote to RAM, meaning the changes vanish after a power cycle.