Chart A4, Code 23 - Left Front Outlet Valve
WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 1990 Pontiac Bonneville, 1990 Oldsmobile Ninety-Eight, 1990 Oldsmobile Eighty-Eight, 1990 Cadillac Fleetwood, and 1990 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
- Normally closed outlet valves are opened by a 12-volt signal from the EBCM on pin No. 16 (left front), 34 (right front) and 33 (rear circuits). The outlet valves are closed only for short periods of time while in the anti-lock mode when pressure holding or pressure reduction is desired for a particular hydraulic circuit.
- Valves have 3 positions: Pressure increase (valves open), pressure hold (inlet valve closed), and pressure reduce (inlet and outlet valves open).
- Valves are self-tested during key "ON" initialization test and also electrically tested while car is driven. Any failure in left front outlet valve circuit will cause Code 23 to set. Anti-lock function is disabled and "ANTI-LOCK" lamp will turn on.