Fix of the week: customers Jeep Grand Cherokee shut off going down the highway and would not start back up. We found that nothing in the ignition system was getting power, upon inspecting the wiring diagram for this vehicle we found that circuit supplied power for many components including the o2 sensors and engine computer. Based on experience we decided to inspect the wiring at the o2 sensor; pictured below is what we found. The o2 sensor wiring was rubbed by the driveshaft shorting out the whole circuit! We repaired this harness and the vehicle sprung back to life!
Talking with the Customer the whole story became clear, the o2 sensor had been recently replaced by a “mechanic” who hadn’t taken the time to properly secure the wiring in its correct location.