Chart A-12, Codes 34/38/44/58/78 - Left Rear Sensor

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Wheel sensors, send a AC signal to EBCM, by passing a toothed ring past 2-pole inductive sensor. EBCM determines calculated wheel speed, using sensor output frequency, to detect wheel lock-up. Resistance of sensor should be 800-1400 ohms.
If cable is damaged, repair or replace cable, using manufacturer repair kit. It is important to maintain original cable twist (6-9 turns per foot).
Any break in continuity in left front wheel sensor circuit will cause one of these Wheel Speed Sensor (WSS) codes to set. The "ANTI-LOCK" lamp may or may not remain on, depending on type of failure.

Fig 1: Flow Chart A-12, Codes 34, 38, 44, 58 or 78 Left Rear Wheel Speed Sensor

Courtesy of GENERAL MOTORS CO.

Fig 2: Flow Chart A-12, Codes 34, 38, 44, 58 or 78 Left Rear Wheel Speed Sensor