1999 LAND ROVER DEFENDER engine

17EMISSION CONTROL
2
REPAIR VALVE - EGR - EU3 MODELS
Service repair no - 17.45.01
Remove
1.Release turnbuckles and remove battery cover.
2.Disconnect battery earth lead.
3.Remove 3 bolts and remove engine acoustic
cover.
4.Remove cooling fan coupling.See COOLING
SYSTEM, Repair.
5.Disconnect vacuum hose(s) from EGR valve.
6.Loosen screw and disconnect air intake hose
from EGR valve.
7.Remove screw and remove clamp securing EGR
pipe to EGR valve.
8.Remove 4 bolts securing EGR valve, remove
valve and discard gasket.
9.Discard EGR pipe gasket.Refit
10.Clean EGR valve and mating faces.
11.Fit new gasket to EGR pipe.
12.Using new gasket, position EGR valve to inlet
manifold fit bolts and tighten to10 Nm (7 lbf.ft).
13.Fit EGR pipe clamp and tighten screw to6Nm
(4.4 lbf.ft).
14.Connect air intake hose to EGR valve and
tighten clip.
15.Connect vacuum hoses to EGR valve.
16.Fit cooling fan coupling.See COOLING
SYSTEM, Repair.
17.Fit engine acoustic cover and tighten bolts to10
Nm (7 lbf.ft).
18.Connect battery earth lead.
19.Fit battery cover and secure the fixings.
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18 - ENGINE MANAGEMENT SYSTEM
CONTENTS
Page
DESCRIPTION AND OPERATION
COMPONENT LOCATION 2...................................................................................
DESCRIPTION 5.....................................................................................................
ENGINE CONTROL MODULE (ECM) 6.................................................................
SENSOR - MASS AIR FLOW (MAF) 7....................................................................
SENSOR - AMBIENT AIR PRESSURE AND 8.......................................................
SENSOR - MANIFOLD ABSOLUTE PRESSURE 9................................................
SENSOR - ENGINE COOLANT TEMPERATURE 11.............................................
SENSOR - CRANKSHAFT SPEED AND 12...........................................................
SENSOR - THROTTLE POSITION (TP) 14............................................................
SENSOR - THROTTLE POSITION (TP) 15............................................................
ELECTRONIC UNIT INJECTOR (EUI) 18...............................................................
SENSOR - FUEL TEMPERATURE (FT) 20............................................................
RELAY - FUEL PUMP 21........................................................................................
RELAY - MAIN 21...................................................................................................
SWITCH - BRAKE PEDAL 22.................................................................................
SWITCH - CLUTCH PEDAL 22...............................................................................
MODULATOR - EXHAUST GAS REGULATOR (EGR) 23.....................................
WARNING LAMP - GLOW PLUG 23......................................................................
GLOW PLUGS 24...................................................................................................
TURBOCHARGER 26.............................................................................................
INTERCOOLER 27.................................................................................................
OPERATION 28......................................................................................................
REPAIR
ENGINE CONTROL MODULE (ECM) 1.................................................................
SENSOR - ENGINE COOLANT TEMPERATURE (ECT) 1....................................
SENSOR - CRANKSHAFT SPEED AND POSITION (CKP) 2................................
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ENGINE MANAGEMENT SYSTEM
1
DESCRIPTION AND OPERATION This page is intentionally left blank
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18ENGINE MANAGEMENT SYSTEM
2
DESCRIPTION AND OPERATION COMPONENT LOCATION
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ENGINE MANAGEMENT SYSTEM
3
DESCRIPTION AND OPERATION 1.Mass Air Flow (MAF) sensor.
2.Engine Coolant Temperature (ECT) sensor.
3.Glow plugs.
4.Manifold Absolute Pressure (MAP) / Inlet Air Temperature (IAT) sensor.
5.Fuel pump relay.
6.Engine Control Module (ECM).
7.Air Conditioning (A/C) and cooling fan relay.
8.Fuel Temperature (FT) sensor.
9.Crankshaft Speed and Position (CKP) sensor.
10.Electronic Unit Injectors (EUI).
11.Ambient Air Pressure (AAP) sensor.
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18ENGINE MANAGEMENT SYSTEM
4
DESCRIPTION AND OPERATION Passenger Compartment
1.Brake pedal switch.
2.Clutch pedal switch.
3.Accelerator pedal switch.
4.Diagnostic connector.
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ENGINE MANAGEMENT SYSTEM
5
DESCRIPTION AND OPERATION DESCRIPTION
General
An engine control module (ECM) controls the five cylinder direct injection diesel engine, and works on the drive by
wire principal. This means there is no throttle cable, the ECM controls the drivers needs via a signal from the
Throttle Position (TP) sensor on the throttle pedal.
The ECM is a full authoritative diesel specific microprocessor that also incorporates features for air conditioning. In
addition, the ECM supplies output control for the Exhaust Gas Recirculation (EGR) and turbocharger boost
pressure. The ECM has a self diagnostic function, which is able to provide backup strategies for most sensor
failures.
The ECM processes information from the following input sources:
Mass Air Flow (MAF) sensor.
Ambient Air Pressure (AAP) sensor.
Manifold Absolute Pressure (MAP) / Inlet Air Temperature (IAT) sensor.
Engine Coolant Temperature (ECT) sensor.
Crankshaft Speed and Position (CKP) sensor.
Throttle Position (TP) sensor.
Fuel Temperature (FT) sensor.
Air conditioning request.
Air conditioning fan request.
Brake pedal switch.
Clutch pedal switch.
The input from the sensors constantly updates the ECM with the current operating condition of the engine. Once
the ECM has compared current information with stored information within its memory, it can make any adjustment
it requires to the operation of the engine via the following:
Air conditioning clutch relay.
Air conditioning cooling fan relay.
Electronic vacuum regulator solenoid.
Fuel pump relay.
Glow plug warning lamp.
Glow plugs.
Fuel injectors.
Main relay.
Turbocharger wastegate modulator.
Temperature gauge.
The ECM interfaces with the following:
Serial communication link.
Instrument pack.
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18ENGINE MANAGEMENT SYSTEM
6
DESCRIPTION AND OPERATION ENGINE CONTROL MODULE (ECM)
The ECM is made from aluminium alloy and is located under the RH front seat. The ECM has an interface of 72
pins via two connectors providing both input information and output control. The ECM receives information from
the sensors to inform it of the current state of the engine. The ECM then refers this information to stored values in
its memory and makes any changes to the operation of the engine necessary via the actuators. This is a rolling
process and is called adaptive strategy. By using this adaptive strategy the ECM is able to control the engine to
give optimum driveability throughout all operating conditions. There is no ECM self test, although the ECM saves
driveability data from the last journey. Power down of the ECM can take between 10 seconds and 10 minutes
dependent on coolant temperature.
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