Hardware Limited Operation Strategy (HLOS)
This system of special circuitry provides minimal engine operation should the PCM [mainly the central processing unit (CPU) or FEEPROM] stop functioning correctly. All modes of Self-Test are not functional at this time. Electronic hardware is in control of the system while in HLOS.
HLOS Allowable Output Functions:
- Spark output controlled directly by the CKP signal.
- Fixed fuel pulse width synchronized with the 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
PCM Location
- Behind instrument panel (cowl), center to both driver and passenger sides.