Land Rover Repair: starting problem freelander td4, engine management systems, instrument pack


Question
john
thank you for your answer to my question

i have had a bit of luck with finding my starting problem. inside the cabin where the fusebox and multifunctionbox for the windows etc. is located there are also some relais. there is a horizontal row and 3 relais are vertical fitted. the bottom one of the vertical ones was faulty and after replacing it the car starts again everytime. if have yet to look into it what it is for but for the sake of £5 the problem is solved. beats taking it to maindealers at £50 an hour.
regards willem

Answer
Willem,

that's very good news.  I wonder which relay it was?  

I will keep this in mind for the next Freelander who has this problem.  

Here is what I have on Freelander Td4 starting:

DESCRIPTION AND OPERATION
CHARGING AND STARTING – Td4 DESCRIPTION

Starting
The starting system on the vehicle comprises a 12 volt starter motor which drives the engine to start the  combustion process. The starter converts electrical energy into mechanical power. The vehicle electrical system must be capable of supplying sufficient power to enable the engine to be cranked.

Charging
The charging system comprises a battery and an alternator. The battery must be of a sufficient capacity to operate the starter motor and operate various electrical systems in the vehicle. The alternator charges the battery when the engine is running and increases its output as demand on the battery increases.

The instrument pack incorporates a charge warning lamp which illuminates when there is no output or a low output from the alternator. For a detailed description of the  charging and starting system, refer to the Engine Management Systems – EDC section of the System Description and Operation Workshop manual.

OPERATION

General
Feed from the positive battery terminal (C0192) is supplied to the main relay, fusible link 1, fusible link 3, fusible link 6, and fuse 10 (C0632) on an R wire. All are located in the engine compartment fuse box. The battery (C0192) also supplies a constant feed to the starter motor solenoid (C0631) on an R wire.

Fusible link 1 is connected in series with fusible link 7, which is also located in the engine compartment fuse box.
Fusible link 3 (C0571) is connected to the ignition switch (C0028) by an N wire. When the ignition switch is turned to the 'ignition' position, current flows across the switch (C0028) to fuse 6, fuse 8, and fuse 19 of the passenger compartment fuse box (C0588) on a G wire.

When the ignition switch is turned to the 'crank' position, current flows across the switch (C0028) to fuse 5 of the passenger compartment fuse box (C0588) on a WR  wire.

Starting
Main Relay
The earth path for the main relay coil (C0576) is controlled by the Engine Control Module (ECM) (C0603) on a WK wire. The energised main relay provides a feed to fuse 1 which is also located in the engine compartment fuse box. Fuse 1 (C0576) provides a feed to the glow plug relay (C0215) on an RW wire.

For a detailed description of main relay operation, refer to the Engine Management Systems – EDC section of the System Description and Operation Workshop manual.

Inertia Switch
Fuse 10 of the engine compartment fuse box (C0575) provides a constant battery feed to the inertia switch  C0123) on a G wire. The inertia switch is a normally closed switch. If the inertia switch hasn't been tripped, current flows across the switch (C0123) to the fuel pump relay coil (C0730) on a GU wire.

The inertia switch (C0123) also provides a feed to the Central Control Unit (CCU) (C0428) on a GU wire. For more information on the CCU, refer to the Control Units section of the Workshop manual, and the Anti-theft Alarm and Central Door Locking (CDL) section of this manual.
+ANTI-THEFT ALARM AND CENTRAL DOOR LOCKING (CDL).

Fuel Pump Relay
The fuel pump relay coil (C0730) receives a feed from the inertia switch (C0123) on a GU wire. The earth path for the relay coil (C0730) is controlled by the ECM (C0331) on a BP wire. The energised fuel pump relay enables a feed from fuse 10 of the engine compartment fuse box (C0575) to flow across the relay switch contacts to the tank mounted fuel pump (C0114) and the secondary fuel pump (C0205) on WP wires. Both pumps are earthed on B wires.

Glow Plug Relay
Fuse 6 of the passenger compartment fuse box (C0581) provides an ignition feed to the ECM (C0603) on a W wire. If all criteria are met, the ECM (C0606) provides an earth path for the glow plug relay coil (C0215) on a BR wire.
Fusible link 6 of the engine compartment fuse box (C0577) provides a constant battery feed to the glow plug relay switch (C0215) on an NW wire.

When the relay is energised, the switch contacts close, allowing the glow plug relay to provide a feed to the following:

To glow plug number 1 (C0476) on a BG wire.
To glow plug number 2 (C0477) on a BP wire.
To glow plug number 3 (C0478) on a BY wire.
To glow plug number 4 (C0479) on a BR wire.

Starter Relay
Fuse 5 of the passenger compartment fuse box (C0581) provides an ignition switch 'crank' feed to the immobilisation ECU (C0059) on a WR wire. If the vehicle has been successfully re-mobilised, the immobilisation ECU (C0059) provides a feed to the starter relay coil (C0576) on an RW wire. The starter relay is located in the engine compartment fuse box, and is earthed (C0576) on a B wire.

A battery feed from fusible link 7 is now able to flow across the starter relay switch contacts (C0572) to the starter motor solenoid (C0178) on an NR then B wire. For a detailed description of the immobilisation ECU, refer to the Engine Immobilisation section of this manual.
+ENGINE IMMOBILISATION.

Starter Motor and Starter Motor Solenoid
The starter motor solenoid coil (C0178) receives a feed from the energised starter motor relay (C0572) on an NR then B wire (see above). The energised starter motor solenoid allows a battery feed (C0178) to flow across the switch contacts and power the starter motor.

Central Control Unit (CCU)
The CCU (C0428) receives a feed from the inertia switch (C0123) on a GU wire. If this feed is removed due to the inertia switch being tripped, the CCU will unlock all of the doors. For more details of CCU operation, refer to the Control Units section of the Workshop manual.

For more details of the Central Door Locking (CDL) system, refer to the Anti-theft Alarm and Central Door Locking (CDL) section of this manual. +ANTI-THEFT ALARM AND CENTRAL DOOR LOCKING (CDL).

NOTE: The CCU will only unlock all doors if the ignition switch is in the 'ignition' position. The CCU (C0429) also provides a signal feed to the immobilisation ECU (C0059) on a KN wire. This signal feed informs the immobilisation ECU to energise the starter relay. For a detailed description of the immobilisation ECU, refer to the Engine Immobilisation section of this manual.

END

Hope this helps,

JohnMc