Charts A-2 To A-4: Main Relay CKT
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 1988 Buick LeSabre, 1988 Buick Electra, 1987 Buick LeSabre, 1987 Buick Electra, and 1986 Buick LeSabre. However, it is still accessible from the selected car via links, so may be relevant.
- Main relay circuit provides battery voltage to ECBM to power main valve, solenoid valves, logic circuit and some self- diagnosis circuits. Main relay coil receives power from ECBM pin No. 8.
- ECBM does not apply power to main relay coil until after ECBM receives ignition enable circuit information. Relay is grounded at ABS ground junction, located on left fender rail. Power for main relay comes through a fusable link from battery junction box.