Jeep Cherokee (XJ): Power grounds. Power steering pressure switch- pcm input. Sensor return-pcm input
OPERATION The Powertrain Control Module (PCM) has 2 main
grounds. Both of these grounds are referred to as
power grounds. All of the high-current, noisy, electrical
devices are connected to these grounds as well as
all of the sensor returns. The sensor return comes
into the sensor return circuit, passes through noise
suppression, and is then connected to the power
ground.
The power ground is used to control ground circuits
for the following PCM loads: DESCRIPTION A pressure sensing switch (Fig. 2) is included in
the power steering system (mounted on the highpressure
line). This switch will be used only on vehicles
equipped with a 2.5L engine and power steering.
1 - POWER STEERING PRESSURE SWITCH OPERATION The power steering pressure switch provides an
input to the Powertrain Control Module (PCM). This
input is provided during periods of high pump load
and low engine rpm; such as during parking maneuvers.
The PCM will then increase the idle speed
through the Idle Air Control (IAC) motor. This is
done to prevent the engine from stalling under the
increased load.
When steering pump pressure exceeds 3275 kPa 6
690 kPa (475 psi 6 100 psi), the normally closed
switch will open and the PCM will increase the
engine idle speed. This will prevent the engine from
stalling. When pump pressure drops to approximately 1379
kPa (200 psi), the switch circuit will re-close and
engine idle speed will return to its previous setting. OPERATION The Sensor Return circuits are internal to the Powertrain
Control Module (PCM).
Sensor Return provides a low-noise ground reference
for all engine control system sensors. Refer to
Power Grounds for more information.Power grounds
Power steering pressure switch-
pcm input
Fig. 2 Power Steering Pump Pressure Switch-2.5L Engine
2 - ELECTRICAL CONNECTOR
3 - POWER STEERING PUMPSensor return-pcm input
Other materials:
Engine accessory drive belts
Fig. 46 Heater and Cord-4.0L 6-Cylinder Engine
1 - POWER CORD LOCATION
2 - BLOCK HEATER
Correct drive belt tension is required to ensure
optimum performance of the belt driven engine accessories.
There are different types of adjustment
gauges for checking either a serpentine or a V-type
...