Bonneville V6-231 3.8L VIN 3 SFI (1988)
ABS Light: Description and Operation
Antilock Warning Lamp Operation
The ABS use "ANTILOCK" warning lamp to alert the vehicle driver that proper antilock braking may not be possible. The main relay will complete the
"ANTILOCK" warning lamp circuit when its control circuit is open. The electrical path for the lamp to light involves a complete circuit when the
ignition switch is in the "crank" or "run" position. The plug-in diode must provide continuity to "ANTILOCK" warning lamp to light under these
conditions. The EBCM will be turned OFF when:
There is no 12-volt power to EBCM terminal 2 ("ignition enable").
The EBCM has detected a circuit problem, and does not complete the main relay control circuit by sending 12-volt power from terminal 8 to the
main relay terminal 2.
The main relay fails to operate.
Lack of 12-volt power to the main relay terminal 4.
If the main relay fails to power up EBCM pins 3 and 20, the EBCM will complete the "ANTILOCK" warning lamp circuit. The EBCM will
complete the "ANTILOCK" warning lamp circuit when it is turned ON and the fluid level sensor or pressure switch contacts open a logic "loop"
circuit. At the same time, the "BRAKE" warning lamp circuit fluid level sensor or pressure switch contacts will close and illuminate the
"BRAKE" warning lamp.