Jeep XJ. Manual — part 528
LEAK DETECTION PUMP (LDP)
The LDP is located in the right-rear side of engine
compartment (Fig. 9). The LDP filter is located above
the LDP (Fig. 9). The LDP and LDP filter are
replaced (serviced) as one unit.
REMOVAL
(1) Carefully remove hose at LDP filter.
(2) Remove LDP filter mounting bolt and remove
from vehicle.
(3) Carefully remove vapor/vacuum lines at LDP.
(4) Disconnect electrical connector at LDP.
(5) Remove 2 LDP mounting screws (Fig. 9) and
remove from vehicle.
INSTALLATION
(1) Install LDP to mounting bracket. Tighten
screws to 1 N·m (11 in. lbs.) torque.
(2) Install LDP filter to mounting bracket. Tighten
bolt to 7 N·m (65 in. lbs.) torque.
(3) Carefully install vapor/vacuum lines to LDP,
and install hose to LDP filter. The vapor/vacuum
lines and hoses must be firmly connected.
Check the vapor/vacuum lines at the LDP, LDP
filter and EVAP canister purge solenoid for
damage or leaks. If a leak is present, a Diagnos-
tic Trouble Code (DTC) may be set.
(4) Connect electrical connector to LDP.
SPECIFICATIONS
TORQUE CHART
Description
Torque
EVAP Canister Mounting Nuts (canister-to-
mounting bracket) . . . . . . . . . 5 N·m (45 in. lbs.)
EVAP Canister Mounting Bracket Nuts (mounting
bracket-to-body) . . . . . . . . . . 43 N·m (32 in. lbs.)
EVAP Canister Purge Solenoid Bracket-to-Body
Mounting Bolt . . . . . . . . . . . . 5 N·m (45 in. lbs.)
LDP Mounting Screws . . . . . . . . 1 N·m (11 in. lbs.)
Fig. 8 EVAP Canister Purge Solenoid (Without LDP)
1 – ELECTRICAL CONNECTOR
2 – VACUUM HARNESS
3 – PURGE SOLENOID
4 – MOUNTING BOLT
Fig. 9 EVAP Canister Purge Solenoid (With LDP)
1 – LDP FILTER
2 – EVAP SOLENOID
3 – EVAP SYSTEM TEST PORT
4 – EVAP SOLENOID ELEC. CONNECTOR
5 – LDP ELEC. CONNECTOR
6 – LDP MOUNTING SCREWS (2)
7 – LDP
8 – LDP MOUNTING BRACKET
25 - 28
EMISSION CONTROL SYSTEMS
XJ
REMOVAL AND INSTALLATION (Continued)
EMISSION CONTROL SYSTEM
TABLE OF CONTENTS
page
page
ON-BOARD DIAGNOSTICS—2.5L DIESEL
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
EXHAUST EMISSION CONTROLS—2.5L
DIESEL ENGINE. . . . . . . . . . . . . . . . . . . . . . . . . . . 6
ON-BOARD DIAGNOSTICS—2.5L DIESEL ENGINE
TABLE OF CONTENTS
page
page
DESCRIPTION AND OPERATION
EMISSION CONTROL SYSTEM—2.5L DIESEL
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
DIAGNOSTIC TROUBLE CODES . . . . . . . . . . . . . . 2
DESCRIPTION AND OPERATION
EMISSION CONTROL SYSTEM—2.5L DIESEL
ENGINE
DESCRIPTION
The 2.5L diesel Engine Control Module (ECM) and
Powertrain Control Module (PCM) monitor and con-
trol many different circuits in the fuel injection pump
and engine systems. If the ECM senses a problem
with a monitored circuit that indicates an actual
problem, a Diagnostic Trouble Code (DTC) will be
stored in the PCM’s memory, and eventually may
illuminate the Check Engine Lamp constantly while
the key is on. If the problem is repaired, or is inter-
mittent, the ECM will erase the DTC after 40
warm-up cycles without the the fault detected. A
warm-up cycle consists of starting the vehicle when
the engine is cold, then the engine is warmed up to a
certain temperature, and finally, the engine tempera-
ture falls to a normal operating temperature, then
the key is turned off.
Certain criteria must be met for a DTC to be
entered into ECM memory. The criteria may be a
specific range of engine rpm, engine or fuel tempera-
ture and/or input voltage to the ECM. A DTC indi-
cates that the ECM has identified an abnormal
signal in a circuit or the system. A DTC may indicate
the result of a failure, but never identify the failed
component directly.
There are several operating conditions that the
ECM does not monitor and set a DTC for. Refer to
the following Monitored Circuits and Non–Monitored
Circuits in this section.
ECM MONITORED SYSTEMS
The ECM can detect certain problems in the elec-
trical system.
Open or Shorted Circuit – The ECM will not
distinguish between an open or a short to ground,
however the ECM can determine if the circuit is
shorted to voltage.
Output Device Current Flow – The ECM senses
whether the output devices are electrically connected.
If there is a problem with the circuit, the ECM
senses whether the circuit is open, shorted to ground
(–), or shorted to (+) voltage.
ECM NON–MONITORED SYSTEMS
The ECM does not monitor the following circuits,
systems or conditions that could have malfunctions
that result in driveability problems. A DTC will not
be displayed for these conditions.
Fuel Pressure: Fuel pressure is controlled by the
fuel injection pump. The ECM cannot detect fuel
pressure problems in this component. The ECM does
a comparison analysis of fuel quantity, fuel timing,
fuel temperature, and control sleeve sensor inputs to
determine if a fuel problem exists.
Cylinder Compression: The ECM cannot detect
uneven, low, or high engine cylinder compression.
XJ
EMISSION CONTROL SYSTEM
25 - 1
2000 JEEP CHEROKEE
Exhaust System: The ECM cannot detect a
plugged, restricted or leaking exhaust system.
Fuel Injector Malfunctions: The ECM cannot
determine if the fuel injector is clogged, or the wrong
injector is installed. The fuel injectors on the diesel
engine are not controlled by the ECM, although a
defective needle movement sensor in the #1 injector
is monitored by the ECM.
Vacuum Assist: Leaks or restrictions in the vac-
uum circuits of the Exhaust Gas Recirculation Sys-
tem (EGR) are not monitored by the ECM.
ECM System Ground: The ECM cannot deter-
mine a poor system ground. However, a DTC may be
generated as a result of this condition.
ECM/PCM Connector Engagement: The ECM
cannot determine spread or damaged connector pins.
However, a DTC may be generated as a result of this
condition.
HIGH AND LOW LIMITS
The ECM compares input signals from each input
device. It has high and low limits that are pro-
grammed into it for that device. If the inputs are not
within specifications and other DTC criteria are met,
a DTC will be stored in memory. Other DTC criteria
might include engine rpm limits or input voltages
from other sensors or switches. The other inputs
might have to be sensed by the ECM when it senses
a high or low input voltage from the control system
device in question.
DIAGNOSTIC TROUBLE CODES
DESCRIPTION
On the following pages, a list of DTC’s is provided
for the 2.5L diesel engine. A DTC indicates that the
ECM has recognized an abnormal signal in a circuit
or the system. A DTC may indicate the result of a
failure, but most likely will not identify the failed
component directly.
ACCESSING DIAGNOSTIC TROUBLE CODES
A stored DTC can be displayed through the use of
the DRB III
t scan tool. The DRB IIIt connects to the
data link connector. The data link connector is
located under the instrument panel near bottom of
the steering column (Fig. 1) (Fig. 2).
ERASING TROUBLE CODES
After the problem has been repaired, use the DRB
III
t scan tool to erase a DTC.
Fig. 1 Data Link Connector Location—LHD
1 – 16–WAY DATA LINK CONNECTOR
Fig. 2 Data Link Connector Location—RHD
1 – DATA LINK CONNECTOR
25 - 2
EMISSION CONTROL SYSTEM
XJ
DESCRIPTION AND OPERATION (Continued)
2000 JEEP CHEROKEE
MSA CONTROLLER DRBIII
T CODES
Generic Scan Tool Code
DRB III
T
Scan Tool Display
P0115
Temperature of Engine Coolant SRC High Exceeded
Temperature of Engine Coolant SRC Low Exceeded
P0180
Fuel Temperature Sensor SRC High Exceeded
Fuel Temperature Sensor SRC Low Exceeded
P0235
Turbocharger Boost Sensor Signal High Exceeded
Turbocharger Boost Sensor Signal Low Exceeded
Turbocharger Boost Sensor Supply High Exceeded
Turbocharger Boost Sensor Supply High Exceeded
Turbocharger Boost Sensor Plausibility
P0400
EGR Open Circuit
EGR Short Circuit
P0500
Veh. Speed Sensor PEC Frequency Too High
Veh. Speed Sensor SRC High Exceeded
Veh. Speed Sensor Plausibility
P0725
Engine Speed Sensor Dyn. Plausibility
Engine Speed Sensor Over Speed Recognition
Engine Speed Sensor Static Plausibilty
P1105
Atmosphere Pressure Sensor SRC High Exceeded
Atmosphere Pressure Sensor SRC Low Exceeded
P1110
Air Temp. Sensor SRC High Exceeded
Air Temp. Sensor SRC Low Exceeded
P1201
Needle Movement Sensor SRC High Exceeded
Needle Movement Sensor SRC Low Exceeded
P1220
Fuel Quantity Actuator Neg Gov Deviation Cold
Fuel Quantity Actuator Neg Gov Deviation Warm
Fuel Quantity Actuator Pos Gov Deviation Cold
Fuel Quantity Actuator Pos Gov Deviation Warm
P1225
Control Sleeve Sensor Signal High Exceeded
Control Sleeve Sensor Start End Pos. Not Attained
Control Sleeve Sensor Stop End Pos. Not Attained
P1230
Timing Governing Negative Governor Deviation
Timing Governing Positive Governor Deviation
P1515
Accel. Pedal Sensor Signal High Exceeded
Accel. Pedal Sensor Supply SRC High Exceeded
Accel. Pedal Sensor Supply SRC Low Exceeded
Accel. Pedal Sensor Plausibility
XJ
EMISSION CONTROL SYSTEM
25 - 3
DESCRIPTION AND OPERATION (Continued)
2000 JEEP CHEROKEE
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст