DTC B1037[12] (Flash Code 44) Leveling Power Supply "Circuit Short to Battery" (Headlight Automatic Leveling Control)

1. DTC B1037[12] description

The headlight leveling actuators are installed to the left and right headlights and have built-in motors. The motors operate in accordance with control voltage supplied from the headlight auto leveling control unit to change the optical axis of the headlights. If the headlight auto leveling control unit determines that optical axis adjustment is required based on headlight leveling sensor signals, a control signal is output to the headlight leveling actuators. The headlight leveling actuators have the following circuits.

  • Power supply circuit
  • Signal circuit
  • Low reference circuit

The headlight auto leveling control unit supplies ignition power to the headlight leveling actuators via the internal circuit, and grounds via the ground circuit. Also, the control signals are output to the headlight leveling actuators via the signal circuit. If the headlight auto leveling control unit detects that the actuator power supply voltage is high when the actuator ON signal is output, the DTC is set.

2. Condition for setting DTC B1037[12]

Condition for running the DTC

  • The ignition switch is ON.
  • The headlight leveling actuators are OFF.

Condition for setting the DTC

  • The headlight auto leveling control unit detects that the headlight leveling actuator power supply voltage is high for 5 seconds or more.

3. Action taken when DTC B1037[12] sets

  • The headlight leveling actuator drive is stopped.
  • The headlight automatic leveling warning light illuminates.