I'll offer that the cold may affect the battery, wiring, and friction-fit metal connections/terminals. Metal expands and contracts proportionately to it's temperature state(s), which may affect the contact points of wiring harnesses and connectors. Albeit perhaps a very fractional difference, this might be part of your issue. Additionally, increasing heat within an electrical system incurs a corresponding increase in the electrical resistance of the system. Conversely, decreasing the temperature will decrease the resistance. Perhaps your decrease in temperature allowed an otherwise failing battery to sustain the necessary amperage for start/boot-up, due to a decrease in system resistance…? …could also be thermal sensor related, keeping extra cold will obviously prevent overheat-protection from being engaged. Decayed thermal paste is likely, and unless you have a verified functional spare battery available, this would be primetime to investigate the heatsink and any / all physical connections. Good luck.

The Reluctor Ring, or commonly called a "tone" ring, is a magnetic feedback device that usually surrounds a vehicle's axle or cv joint in the vicinity of the brake at each wheel. It is easily identified as a ring with notches cut into it, commonly about a half inch wide or slightly less, and 4.5-6" in diameter, depending on the size of the axle or cv joint in the vehicle. The "nodes" in the ring (spaces between the notches, pass by the magnet in the wheel speed sensor(s) that sits at a specific distance from the ring, creating an electrical impulse that is sent to the ABS controller, or Brake Control Module (BCM). The ring and sensor count the nodes as they pass and calculate the wheel speed at the brake of each wheel. The vehicle speed sensor, in turn, should correspond with the reading at the wheel. The only time these values are NOT equal is when a wheel is locked up and sliding under hard braking conditions. In this condition, the BCM recognizes the values as inequal, and it engages the servo at the...