DTC C0200/31: Front Speed Sensor RH Circuit; DTC C0205/32: Front Speed Sensor LH Circuit; DTC C1271/71: Low Output Signal of Front Speed Sensor RH (Test Mode DTC); DTC C1272/72: Low Output Signal of Front Speed Sensor LH (Test Mode DTC): Description

The speed sensors detect the wheel speeds and send appropriate signals to the skid control ECU. Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change as the rotors turn.

The speed sensors detect those magnetic changes and send pulse signals to the skid control ECU. The ECU monitors the wheel speeds through these pulse signals to control the ABS control system.

DTCs C1271/71 and C1272/72 can be deleted when the speed sensor sends a vehicle speed signal or the Test Mode ends. DTCs C1271/71 and C1272/72 are output only in the Test Mode.

Fig 1: Speed Sensor Voltage Graph

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

When testing voltage, perform the test while the connector between the sensor and ECU is connected. Do not disconnect the connector between the sensor and ECU.

DTC Code	DTC Detection Condition	Trouble Area
C0200/31 C0205/32	When any of the following is detected: At a vehicle speed of 10 km/h (6 mph) or more, an open or short in the sensor signal circuit continues for 1 second or more. Momentary interruption of the sensor signal from the abnormal wheel occurs 255 times or more. An open in the speed sensor signal circuit continues for 0.5 seconds or more. With the IG1 terminal voltage 9.5 V or more, the sensor power supply voltage decreases for 0.5 seconds or more.	Front speed sensor RH/LH Speed sensor circuit Speed sensor rotor Sensor installation Brake actuator assembly (Skid control ECU)
C1271/71 C1272/72	Detected only during Test Mode.	Front speed sensor RH/LH Sensor installation Speed sensor rotor

HINT:

DTCs C0200/31 and C1271/71 are for the front speed sensor RH.
DTCs C0205/32 and C1272/72 are for the front speed sensor LH.