Circuit Description

The Electronic Brake and Traction Control Module (EBTCM) determines rough road surfaces using input from wheel speed sensors. EBTCM then sends the rough road data to the PCM via the Class II serial data. PCM uses this data to enhance misfire diagnostic. Data allows PCM to distinguish the crankshaft speed variations caused by rough road surfaces from those caused by true misfires. DTC will set if a loss of communication occurs causing PCM not to receive rough road information while a misfire condition is requesting MIL.