Land Rover Freelander 2004my Electrical Library Rover Manual

							DESCRIPTION AND OPERATION
4.62FREELANDER 04MY
EAT ECU
The EAT ECU monitors the operation of the automatic gearbox via four sensors:
zThe temperature of the automatic transmission fluid (ATF) is measured by the fluid 
temperature sensor. The fluid temperature sensor (C0243) receives a feed from the 
EAT ECU (C0932) on a WK wire. The temperature sensor return (C0243) to the EAT 
ECU (C0932) is via a KB wire. As the temperature of the ATF rises, so the resistance 
of the sensor decreases. The EAT ECU registers this drop in resistance and calculates 
the temperature of the ATF accordingly. For more information on the fluid temperature 
sensor, refer to the  Automatic Gearbox – Jatco  section of the System Description 
and Operation Workshop manual.
zVehicle speed is measured by the vehicle speed sensor. The vehicle speed sensor 
(C0243) is connected to the EAT ECU (C0932) by a U wire. The speed sensor creates 
a sinusoidal waveform, with each positive phase of the waveform representing one 
tooth on the parking gear (19 per engine revolution). The EAT ECU uses this waveform 
to calculate vehicle speed. The sensor return (C0243) to the EAT ECU (C0932) is via 
a W then KB wire. For more information on the vehicle speed sensor, refer to the  
Automatic Gearbox – Jatco  section of the System Description and Operation 
Workshop manual.
zInput shaft speed into the gearbox is measured by the turbine sensor. The turbine 
sensor (C0243) is connected to the EAT ECU (C0932) by an R wire. The turbine 
sensor creates a sinusoidal waveform, with 16 positive phases representing one input 
shaft revolution. The EAT ECU uses this signal along with a vehicle speed signal to 
calculate if the correct gear has been selected. The sensor return (C0243) to the EAT 
ECU (C0932) is via a U then KB wire. For more information on the turbine sensor, refer 
to the  Automatic Gearbox – Jatco  section of the System Description and Operation 
Workshop manual.
zThe internal, or intermediate, transmission speed is measured by the intermediate 
sensor. The intermediate sensor (C0243) is connected to the EAT ECU (C0932) by an 
R wire. The intermediate sensor creates a sinusoidal waveform, with each positive 
phase of the waveform representing one tooth of the output gear (49 per revolution). 
The EAT ECU uses this signal to ensure the correct gear is engaged, and to monitor 
the amount of slip within the gearbox. The sensor return (C0243) to the EAT ECU 
(C0932) is via a B then KB wire. For more information on the intermediate sensor, refer 
to the  Automatic Gearbox – Jatco  section of the System Description and Operation 
Workshop manual. 
						

							DESCRIPTION AND OPERATION
FREELANDER 04MY 4.63
Park
When park is selected, a main relay feed is able to flow from the transmission selector/inhibit 
switch (C0244) to the EAT ECU (C0932) and the selector indicator (C0675) on a KO wire. 
The P symbol on the selector housing will now illuminate.
NOTE: On Canadian specification vehicles, a feed is also provided to the Central Control 
Unit (CCU) (C0593) on a KO wire. This input is used by the CCU to extinguish the daylight 
running lamps.
Reverse
When reverse gear is selected, a main relay feed is able to flow from the transmission 
selector/inhibit switch (C0244) to  the reverse lamp relay (C2624) on an NG wire. The 
reverse lamp relay (C0935) is earthed on a B wire and controls operation of the reverse 
lamps. For more information on reverse lamp operation, refer to the  Brake and Reverse 
Lamps  section of this manual.
 
+  BRAKE AND REVERSE LAMPS. 
A main relay feed is also supplied to the EAT ECU (C0932) and the selector indicator 
(C0675) on NG wires. The R symbol on the selector housing will now illuminate.
If the vehicle is travelling forwards at greater than 6 mph (10 kph), the EAT ECU (C0932) 
provides a feed to the Low Coast solenoid (C0243) on a K wire. The Low Coast solenoid 
(C0243) is earthed via the EAT ECU (C0932) on an SB wire. When the Low Coast solenoid 
receives this feed, it drains the transmission fluid from the reverse clutch, thus preventing 
reverse gear from being selected.
Neutral
When neutral is selected, a main relay feed is able to flow from the transmission selector/
inhibit switch (C0244) to the EAT ECU (C0932) and the selector indicator (C0675) on a WU 
wire. The N symbol on the selector housing will now illuminate.
Drive
When drive is selected, a main relay feed is able to flow from the transmission selector/
inhibit switch (C0244) to the EAT ECU (C0932) and the selector indicator (C0675) on a WB 
wire. The D symbol on the selector housing will now illuminate.
When drive is selected, the EAT ECU (C0932) receives signals from the vehicle speed 
sensor (C0243) housed within the gearbox on a U wire. The sensor (C0243) is earthed via 
EAT ECU (C0932) on a W then KB wire. The EAT ECU (C0932) also receives a throttle 
pedal signal from the ECM (C0331 on Td4 and KV6 NAS vehicles, C0371 on KV6 ROW 
vehicles) via the CAN-BUS on YN (Low) and YB (High) wires. The EAT ECU uses this 
information to select the appropriate gear by operating the gearbox shift solenoids as 
follows: 
						

							DESCRIPTION AND OPERATION
4.64FREELANDER 04MY
1st Gear
To select first gear, shift solenoid B and shift solenoid C are operated. The EAT ECU 
(C0932) will provide a feed to shift solenoid B (C0243) on an O wire. Shift solenoid C 
(C0243) receives a feed from the EAT ECU (C0932) on an OU wire.
2nd Gear
To select second gear, shift solenoid A and shift solenoid B are operated. The EAT ECU 
(C0932) will provide a feed to shift solenoid A (C0243) on an R wire. Shift solenoid B 
(C0243) receives a feed from the EAT ECU (C0932) on an O wire.
3rd Gear
To select third gear, only shift solenoid B is operated. The EAT ECU (C0932) will provide a 
feed to shift solenoid B (C0243) on an O wire.
4th Gear
To select fourth gear, only shift solenoid C is operated. The EAT ECU (C0932) will provide 
a feed to shift solenoid C (C0243) on an OU wire.
5th Gear
To select fifth gear, shift solenoid A and shift solenoid C are operated. The EAT ECU 
(C0932) will provide a feed to shift solenoid A (C0243) on an R wire. Shift solenoid C 
(C0243) receives a feed from the EAT ECU (C0932) on an OU wire.
4
When 4 is selected, a main relay feed is able to flow from the transmission selector/inhibit 
switch (C0244) to the EAT ECU (C0932) and the selector indicator (C0675) on an RG wire. 
The 4 symbol on the selector housing will now illuminate.
When 4 is selected, only the lowest 4 gears will be operable. For more information, refer to 
the  Drive  section.
2
When 2 is selected, a main relay feed is able to flow from the transmission selector/inhibit 
switch (C0244) to the EAT ECU (C0932) and the selector indicator (C0675) on an OB wire. 
The 2 symbol on the selector housing will now illuminate.
When 2 is selected, only the lowest 2 gears will be operable. For more information, refer to 
the  Drive  section.
1
When 1 is selected, a main relay feed is able to flow from the transmission selector/inhibit 
switch (C0244) to the EAT ECU (C0932) and the selector indicator (C0675) on a GY wire. 
The 1 symbol on the selector housing will now illuminate.
When 1 is selected, only first gear will be operable. For more information, refer to the  Drive  
section. 
						

							DESCRIPTION AND OPERATION
FREELANDER 04MY 4.65
Mode Selection
Sport Mode
The selector lever (C0410) is provided a main relay feed via fuse 4 of the engine 
compartment fuse box (C0575) on an NK wire. When the lever is moved across to the S/M 
position, the selector lever (C0410) provides a feed to the EAT ECU (C0932) on an LGK 
wire. The EAT ECU will now enter sport mode. In sport mode, the gearbox still operates as 
a conventional automatic transmission, but the unit becomes more responsive to driver 
demands. The selector lever (C0410) is earthed on a B wire.
The selector lever (C0410) also provides a feed to the selector indicator (C0675) on an LGK 
wire, illuminating the S/M symbol on the selector housing.
Manual (CommandShift) Mode
When in sport mode, if the selector lever is moved to the + or - positions, the gearbox will 
automatically enter manual (CommandShift) mode. When the selector lever is moved to the 
- position, it provides a feed to the EAT ECU (C0932) on a GK wire. When the selector lever 
is moved to the + position, it provides a feed to the EAT ECU (C0932) on a GB wire. Manual 
gear changes can now be performed sequentially using the selector lever.
Cruise Control Mode – Td4 and NAS
The cruise control master switch is located on the drivers side of the fascia. When cruise 
control is activated, the cruise control interface unit (C0895) provides a feed to the EAT ECU 
(C0932) on a WU wire. In cruise control mode, the EAT ECU uses a dedicated gearshift map 
to control the gearbox and assist the cruise control ECU in maintaining the vehicle speed at 
the required level.
For more information on cruise control operation, refer to the  Cruise Control – Td4 & KV6 
(North America)  section of this manual.
 
+  CRUISE CONTROL – TD4 & KV6 (NORTH AMERICA). 
Cruise Control Mode – KV6
The cruise control master switch is located on the drivers side of the fascia. When cruise 
control is activated, the cruise control ECU (C0239) provides a feed to the EAT ECU 
(C0932) on a WU wire. In cruise control mode, the EAT ECU uses a dedicated gearshift map 
to control the gearbox and assist the cruise control ECU in maintaining the vehicle speed at 
the required level.
For more information on cruise control operation, refer to the  Cruise Control – KV6  section 
of this manual.
 
+  CRUISE CONTROL – KV6.  
						

							DESCRIPTION AND OPERATION
4.66FREELANDER 04MY
Hill Descent Control (HDC) Mode
In HDC mode, the EAT ECU applies engine braking to assist the ABS ECU in controlling the 
vehicles descent. HDC mode is activated if all of the following conditions exist:
zThe gear selector lever is in position 1 or R.
zThe HDC switch is depressed.
zThe throttle pedal is released.
The EAT ECU (C0932) communicates with the ABS ECU (C0501) via the CAN-BUS on YB 
(High) and YN (Low) wires. For more information on the CAN-BUS, refer to the  
Communication Databuses  section of the System Description and Operation Workshop 
manual.
Fluid Pressure Control
Fluid pressure within the automatic gearbox is controlled by the Line Pressure duty solenoid. 
When required, the EAT ECU (C0932) provides a Pulse Width Modulated (PWM) signal to 
the Line Pressure duty solenoid (C0243) on a Y wire. The solenoid (C0243) is earthed via 
the EAT ECU (C0932) on an SB wire. For more details on fluid pressure control, refer to the   
Automatic Gearbox – Jatco   section of the System Description and Operation Workshop 
manual.
Torque Converter Lock-Up
When the gearbox is in 4th or 5th gear, and the EAT ECU registers a high vehicle speed 
combined with a small throttle angle, the EAT ECU will lock the torque converter. This will 
enable maximum power to be transmitted to the road wheels. When this occurs, the EAT 
ECU (C0932) provides a PWM signal to the Lock-Up duty solenoid (C0243) on a U wire. The 
solenoid (C0243) is earthed via the EAT ECU (C0932) on an SB wire. For more details on 
torque converter lock-up, refer to the   Automatic Gearbox – Jatco   section of the System 
Description and Operation Workshop manual.
Shift Interlock
When the ignition switch is in the ignition position and the selector lever is in the Park, the 
EAT ECU (C0932) provides a feed to the shift interlock solenoid (C0268) on a GW wire 
locking the selector lever in the Park position. When the brake pedal is pressed, the brake 
pedal switch (C0652) provides a feed to the EAT ECU (C0932) on a GR wire. Sensing the 
brake pedal has been pressed the EAT ECU withdraws the feed to the shift interlock 
solenoid, releasing the selector lever.
The shift interlock solenoid (C0268) is earthed on a B wire. 
						

							DESCRIPTION AND OPERATION
FREELANDER 04MY 4.67
Diagnostic Socket
If the EAT ECU detects a failure in an associated component, a fault code will be stored in 
its memory. TestBook or T4 can be used via the diagnostic socket to retrieve these fault 
codes to identify the cause of the failure. The diagnostic socket (C0040) is connected to the 
EAT ECU (C0932) by a K wire. 
						

							DESCRIPTION AND OPERATION
4.68FREELANDER 04MY
ANTI-LOCK BRAKING SYSTEM (ABS)
DESCRIPTION
General
The ABS is a full time, four channel system that gives individual speed control to all four 
wheels to provide the vehicle with anti-lock braking (ABS), Electronic Traction Control 
(ETC), and Hill Descent Control (HDC). The systems are controlled by the ABS ECU, which 
is mounted on the rear of the ABS modulator. The ABS ECU also controls the front to rear 
brake balance by Electronic Braking force Distribution (EBD). This maximises vehicle 
stability under braking.
For a detailed description of ABS, ETC HDC, and EBD, refer to the  Brakes  section of the 
System Description and Operation Workshop manual.
The ABS modulator uses the CAN-BUS to communicate with other ECUs to enable it to 
control braking more efficiently. For more information on the CAN-BUS, refer to the  
Communication Databuses  section of the System Description and Operation Workshop 
manual.
OPERATION
General
Feed from the positive battery terminal (C0192) is supplied to fusible link 1, fusible link 3, 
fusible link 8, and fusible 11 (C0632) on an R wire. All are located in the engine compartment 
fuse box.
Fusible link 8 (C0574) and fusible link 11 (C0570) provide constant battery feeds to the ABS 
modulator (C0501) on NK and NR wires respectively. The ABS modulator (C0501) is 
earthed on a pair of B wires.
Fusible link 1 is connected in series with fusible link 2, which is also located in the engine 
compartment fuse box. Fusible link 2 (C0571) provides a feed to the ignition switch (C0028) 
on an NR wire. Fusible link 3 (C0571) also provides a feed to the ignition switch (C0028) on 
an N wire.
When the ignition switch is turned to the ignition position, current flows across the switch 
(C0028) to fuse 2 of the passenger compartment fuse box (C0588) on an NW wire. When in 
the ignition position, the ignition switch (C0028) also provides a feed to fuse 6 and fuse 25 
of the passenger compartment fuse box (C0588) on a G wire.
Fuse 2 of the passenger compartment fuse box (C0581) provides an ignition feed to the 
brake pedal switch (C0075) on a G wire. Fuse 2 also provides a feed to the HDC relay and 
the reverse lamp relay, which are also located in the passenger compartment fuse box.
Fuse 25 (C0582) provides an ignition feed to the ABS ECU (C0501) on a W wire. Fuse 6 
(C0581) provides an ignition feed to the HDC switch (C0878) on a W wire. 
						

							DESCRIPTION AND OPERATION
FREELANDER 04MY 4.69
Wheel Speed Sensors
The ABS ECU (C0501) supplies a feed to all four wheel speed sensors as follows:
zTo the LH front wheel speed sensor (C0516) on an R wire.
zTo the RH front wheel speed sensor (C0517) on a Y wire.
zTo the LH rear wheel speed sensor (C0502) on a G wire.
zTo the RH rear wheel speed sensor (C0503) on a W wire.
The wheel speed sensors provide the ABS ECU with a square wave form signal. By 
measuring the frequency of the wave form, the ABS ECU can calculate the speed of the road 
wheel. The sensors provide the ABS ECU (C0501) with wheel speed signals as follows:
zFrom the LH front wheel speed sensor (C0516) on an RB wire.
zFrom the RH front wheel speed sensor (C0517) on a YB wire.
zFrom the LH rear wheel speed sensor (C0502) on a GB wire.
zFrom the RH rear wheel speed sensor (C0503) on a WB wire.
If the ABS ECU detects wheel deceleration is too great, it will initiate the ABS. If the ABS 
ECU detects that wheel speed is greater than vehicle speed, it will initiate ETC. If HDC is 
operational, the ABS ECU will control vehicle speed at 7 mph (11 km/h) by applying the 
brakes where necessary. For more information on ABS, ETC, and HDC, refer to the  Brakes  
section of the System Description and Operation Workshop manual.
ABS ECU
Td4 – Manual Transmission
The ABS ECU (C0501) provides a road wheel speed signal to the Engine Control Module 
(ECM) (C0331) via the CAN BUS on YN (low) and YB (high) wires.
Td4 – Automatic Transmission
The ABS ECU (C0501) provides a road wheel speed signal to the Electronic Automatic 
Transmission Electronic Control Unit (EAT ECU) (C0932) via the CAN BUS on YN (low) and 
YB (high) wires.
K1.8
The ABS ECU (C0501) provides a road wheel speed signal to the Engine Control Module 
(ECM) (C0913) via the CAN BUS on YN (low) and YB (high) wires.
KV6
The ABS ECU (C0501) provides a road wheel speed signal to the EAT ECU (C0932) via the 
CAN BUS on YN (low) and YB (high) wires. This information is relayed to the ECM (C0371) 
via the CAN BUS on YN (low) and YB (high) wires.
For more information on the CAN BUS, refer to the  Communication Databuses  section 
of the System Description and Operation Workshop manual.
The ABS ECU (C0501) also provides a pulsed road speed signal to the CCU (C0428) on a 
WO wire. 
						

							DESCRIPTION AND OPERATION
4.70FREELANDER 04MY
Brake Pedal Switch
The brake pedal switch is a double contact mechanical switch, mounted at the top of the 
brake pedal adjacent the brake pedal sensor. The switch (C0075) is provided an ignition 
feed from fuse 2 of the passenger compartment fuse box (C0582) on a G wire. When the 
brake pedal is at rest, the switch (C0075) provides a feed to the ABS ECU (C0501) on a GR 
wire. When the brake pedal is pressed, the switch (C0075) informs the ABS ECU (C0501) 
by providing a feed on a GP wire.
When the brake pedal is pressed, the switch (C0075) also provides a feed to the following 
on GP wires:
zThe LH brake lamp (C0121).
zThe RH brake lamp (C0125).
zThe Centre High Mounted Stop Lamp (CHMSL) (C0613).
zThe trailer pick-up (C0499) on a GP then R wire.
For more information on brake lamp operation, refer to the  Brake and Reverse Lamps  
section of this manual.
 
+  BRAKE AND REVERSE LAMPS. 
Accelerometer
The accelerometer is mounted beneath the centre console adjacent the handbrake, and 
provides the ABS ECU additional information regarding vehicle motion. The ABS ECU 
(C0501) provides a feed to the accelerometer (C1220) on a Y wire. The sensor (C1220) 
returns a vehicle acceleration/deceleration signal to the ABS ECU (C0501) on an R wire.
The accelerometer (C1220) is provided an earth path via the ABS ECU (C0501) on a U wire. 
Brake Fluid Level Switch
The ABS ECU (C0501) provides a feed to the brake fluid level switch (C0026) on a BW wire. 
The switch is closed when the correct amount of brake fluid is present in the brake fluid 
reservoir. The switch (C0026) is earthed on a B wire. If the brake fluid level drops below the 
recommended level, the switch contacts open. When the ABS ECU registers the switch 
opening, it informs the instrument pack (C0230) to illuminate the brake fluid warning lamp 
via the CAN-BUS on YN (low) and YB (high) wires.
For more information on warning lamp operation, refer to the  Instruments  section of this 
manual.
 
+  INSTRUMENTS.  
						

							DESCRIPTION AND OPERATION
FREELANDER 04MY 4.71
Hill Descent Control (HDC)
HDC Switch
The HDC switch (C0878) is mounted on the gear lever, and informs the ABS ECU (C0501) 
when HDC has been selected. When HDC is selected, the switch contacts close, and a feed 
is provided to the ABS ECU (C0501) on a PS wire. When the ABS ECU receives this feed, 
it energises the HDC relay.
NOTE: The ABS ECU will only initiate HDC if either 1st or reverse gear are selected, and 
brake temperature doesnt exceed 400 
°C (752 °F).
1st Gear Switch (Manual Transmission)
The 1st gear switch (C0618) is mounted in the gearbox, and informs the ABS ECU (C0501) 
when 1st gear has been selected. The Instrument pack (C0230) provides a feed to the 
switch (C0618) on an RW wire (RW then GB on K1.8 vehicles). When 1st gear is selected, 
the instrument pack (C0230) informs the ABS ECU (C0501) via the CAN BUS on YN (low) 
and YB (high) wires. The switch (C0618) is earthed on a B wire.
HDC Relay
The HDC relay (C2624) is located in the passenger compartment fuse box, and is controlled 
by the ABS ECU (C0501) on a BR wire. When energised, the HDC relay (C2624) provides 
a feed to the following on GP wires:
zThe ABS ECU (C0501).
zThe LH brake lamp (C0121).
zThe RH brake lamp (C0125).
zThe CHMSL (C0613).
zThe trailer pick-up (C0499) on GP then R wire.
Diagnostic Socket
The diagnostic socket (C0040) is connected to the ABS ECU (C0501) by a K wire, enabling 
the ABS ECU to be interrogated by TestBook or T4.