Jeep Cherokee (XJ): Description and operation
Jeep Cherokee (XJ) 1984 - 2001 Service Manual > Fuel system > Fuel injection system > Description and operation
- Powertrain control module (PCM)
- Modes of operation
- Automatic shutdown (asd) relay sense-pcm input. Battery voltage-pcm input. Brake switch-pcm input
- Five volt sensor supplies-primary and secondary. Fuel level sensor-pcm input. Engine coolant temperature sensor-pcm input
- Extended idle switch-pcm input. Oxygen sensor-pcm input. Ignition circuit sense-pcm input
- Intake manifold air temperature sensor-pcm input. Manifold absolute pressure (map) sensor-pcm input. Oil pressure sensor-pcm input
- Power grounds. Power steering pressure switch- pcm input. Sensor return-pcm input
- Throttle position sensor (tps)-pcm input. Vehicle speed and distance sensor- pcm input. Auto shutdown (asd) relay-pcm output
- CCD bus (+/-) circuits-pcm outputs. Data link connector-pcm input and output. Fuel injectors-pcm output
- Fuel pump relay-pcm output. Idle air control (iac) motor-pcm output. Radiator fan relay-pcm output
- Throttle body
Powertrain control module (PCM)
DESCRIPTION
The Powertrain Control Module (PCM) is located
in the engine compartment (Fig. 1). The PCM is
referred to as JTEC.
OPERATION
The PCM operates the fuel system. The PCM is a
pre-progra ...
Other materials:
Diagnosis and testing
Fuel pump pressure test
Use this test in conjunction with the Fuel Pump
Capacity Test, Fuel Pressure Leak Down Test and
Fuel Pump Amperage Test found elsewhere in this
group.
Check Valve Operation: The electric fuel pump
outlet contains a one-way check valve to prevent fuel
flow back into th ...