Jeep Cherokee 2000 Service Manual - page 1261
engine in one of the three “limp-in” modes. When the
PCM is operating in this mode, a loss of power will
be present, as if the turbocharger was not operating.
The best method for diagnosing faults with the boost
pressure sensor is with the DRB III scan tool. Diag-
nostic Trouble Codes: Refer to On-Board Diagnos-
tics in Group 25, Emission Control System for a list
of Diagnostic Trouble Codes (DTC’s) for certain fuel
system components.
VEHICLE SPEED SENSOR TEST
To perform a test of the sensor and its related cir-
cuitry, refer to DRB scan tool.
Diagnostic Trouble Codes: Refer to On-Board
Diagnostics in Group 25, Emission Control System
for a list of Diagnostic Trouble Codes (DTC’s) for cer-
tain fuel system components.
DIAGNOSTIC TROUBLE CODES
For a list of Diagnostic Trouble Codes (DTC’s),
refer to Group 25, Emission Control System for infor-
mation. See On-Board Diagnostics.
REMOVAL AND INSTALLATION
ASD RELAY
The ASD relay is located in the PDC. For the loca-
tion of the relay within the PDC, refer to label on
PDC cover.
A/C CLUTCH RELAY
The A/C clutch relay is located in the PDC. For the
location of the relay within the PDC, refer to label on
PDC cover.
ENGINE SPEED SENSOR
The engine speed sensor is mounted to the trans-
mission bellhousing at the rear of the engine block
(Fig. 21).
REMOVAL
(1) Disconnect the harness (on the sensor) from
the main electrical harness.
(2) Remove the sensor mounting bolts.
(3) Remove the sensor.
INSTALLATION
(1) Install the sensor flush against the opening in
the transmission housing.
(2) Install and tighten the sensor mounting bolt to
19 N·m (14 ft. lbs.) torque.
(3) Connect the electrical connector to the sensor.
ENGINE COOLANT TEMPERATURE SENSOR
The sensor is located on the side of cylinder head
near the rear of fuel injection pump.
REMOVAL
WARNING: HOT,
PRESSURIZED
COOLANT
CAN
CAUSE INJURY BY SCALDING. COOLING SYSTEM
MUST BE PARTIALLY DRAINED BEFORE REMOV-
ING
THE
COOLANT
TEMPERATURE
SENSOR.
REFER TO GROUP 7, COOLING.
(1) Partially drain cooling system. Refer to Group
7, Cooling.
(2) Disconnect electrical connector from sensor.
(3) Remove sensor from cylinder head.
INSTALLATION
(1) Install a new copper gasket to sensor.
(2) Install sensor to cylinder head.
(3) Tighten sensor to 18 N·m (13 ft. lbs.) torque.
(4) Connect electrical connector to sensor.
(5) Replace any lost engine coolant. Refer to Group
7, Cooling System.
GLOW PLUGS
The glow plugs are located above each fuel injector
(Fig. 22). Four individual plugs are used.
REMOVAL
(1) Disconnect the negative battery cable at the
battery.
(2) Clean the area around the glow plug with com-
pressed air before removal.
Fig. 21 Engine Speed Sensor
1 – ENGINE SPEED SENSOR
2 – GROMMET
3 – MOUNTING BOLT(S)
4 – LEFT REAR OF ENGINE
5 – TRANSMISSION
XJ
FUEL SYSTEM—2.5L DIESEL ENGINE
14 - 35
DIAGNOSIS AND TESTING (Continued)