Hardware Limited Operation Strategy
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2003 Mercury Sable, 2003 Mercury Mountaineer, 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
HLOS is a system of alternate circuitry that provides minimal engine operation if the PCM or EEPROM fails. During HLOS, all self-test function will stop and system will be controlled by electronic hardware.
HLOS Allowable Output Functions:
- Spark Output Controlled Directly By CKP Signal
- Fixed Fuel Pulse Width Synchronized With CKP Signal
- Fuel Pump Relay Energized
- Idle Speed Control Output Signal Functional
HLOS Disabled Outputs To Default State:
- EGR Solenoids
- No Torque Converter Clutch Lock-Up