Powertrain Control Hardware

Powertrain Control Hardware

Smart Junction Box (SJB)

Keep Alive Random Access Memory (RAM)
The PCM stores information in keep alive RAM (a memory integrated circuit chip) about vehicle operating conditions, and then uses this information to compensate for component variability. Keep alive RAM remains powered when the ignition switch is off so that this information is not lost.

Hardware Limited Operation Strategy (HLOS)
This system of special circuitry provides minimal engine operation should the PCM [mainly the central processing unit (CPU) or EEPROM] 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
- In the engine compartment, at the rear of the engine above the center of the cowl

Integrated Electronic Ignition System
The item grated electronic ignition (El) system consists of a crankshaft position (CKP) sensor, coil pack(s), connecting wire, and PCM. The coil on plug (COP) integrated El system uses a separate coil for each spark plug and each coil is mounted directly onto the plug. The COP integrated El system eliminates the need for spark plug wires but does not require input from the camshaft position (CMP) sensor.