Circuit Description

When ignition switch is first turned to RUN position, EBCM/EBTCM goes through a self-check, which lasts 2-4 seconds. During self-check, EBCM/EBTCM grounds terminal No. 34 to energize main relay. After self-check is completed, main relay remains energized.

With main relay energized, battery voltage is delivered to EBCM/EBTCM and Pressure Modulator Valve (PMV) during vehicle operation. Constant battery voltage allows vehicle to enter ABS mode without delay. If Amber ANTI-LOCK warning light comes on because of a system fault, main relay will be de-energized, causing ABS system to shut down.