Please find attached both an overview manual for the Bosch M5.2.1 engine computer, very informative; and a larger guide split into three sections that details the trouble codes for each system and how they are calculated. These would apply to a D2 and some other vehicles.

If you are looking for D1, see https://landroverforums.com/forum/di...-manual-47986/

aka ECU, ECM, computer, CPU, Bosch M5.2.1

 

Excellent info savannah, much appreciated and now on my rave usb stick. Thanks

 

Thanks for this

Very useful stuff

medic

 

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Looks like as soon as the ENGINE COMPUTER ECM is powered up, the fuel system should pressuize to 2.5 BAR of pressure.

That means-
key on

You need to have a fuel pump that RAN and pressurized the system..

If you take off the FUEL pipe - to the injector fuel ring - there should be fuel pressure - a squirt of fuel should appear. Don't do this with the KEY ON.




Make sure the Crank sensor is close enough..



4.10 Camshaft Position Sensor
4.10.1 Description
This is a Hall effect sensor producing four pulses for every two engine revolutions. The sensing element is positioned between 0 and 2mm from the
side of the cam gear wheel. The sensor is, in effect, a magnetically operated electrical switch, switching a battery supply level voltage on or off
dependent on the position of the cam gear wheel with respect to the sensor.

!!!!!!!!!!!!!!!!!!!!!!!!!!
Make sure your ECM is on the CAN BUSS

The ECM performs a number of self-test integrity diagnostics on its internal hardware and software to check for faults. An error is detected if the ECM
receives no CAN messages for at least 0.8 seconds, the calculated checksums at power down do not match the values stored in flash Electrically
Erasable Programmable Read Only Memory (EEPROM) or the internal or external RAM fails a read/write test.


POWER

4.18 Power Supplies
4.18.1 Description
The ECM requires a permanent battery level voltage supply and a switched battery level voltage supply. The switched voltage supply is controlled by
the ECM via a relay based on the condition of the ignition switch input (key position 2). At “key off” the ECM will maintain the switched supply active
until various internal self-checks have been completed.
There are three battery voltage plausibility checks during which a fault is detected if: -
1. The battery voltage supply is less than a minimum voltage threshold.
2. The battery voltage supply is greater than a maximum voltage threshold and a jump-start condition has not been detected.
3. The battery voltage supply is less than a voltage threshold 60 seconds after the engine has been started.


FUEL PUMP RELAY

4.24 Fuel Pump Relay
4.24.1 Description
The Land Rover V8 engine has a return-less fuel system. The fuel pressure regulator and filter are fitted to the .in tank fuel pump module.. The system
pressure is maintained at a constant 3.5 bar (52 Psi), with no reference to intake manifold pressure. The ECM compensates for the non-constant
pressure drop across the injector nozzles.
The fuel is supplied to the injectors from a fuel pump fitted within the fuel tank. The electrical supply to this fuel pump is controlled by the ECM via a
relay and an Inertia fuel shutoff switch, which will turn off the fuel supply upon vehicle impact. The fuel system is pressurised to 3.5 bar as soon as the
ECM is powered up, the pump is then switched off until engine start has been achieved. If the pump runs but the fuel pressure is out of limits,
adaptive fuel faults are stored.
The ECM monitors the output power stage of the fuel pump relay drive for electrical faults. A fault is detected if any of the following conditions is
satisfied: -
1. Fuel pump relay driver short circuit to battery positive, i.e. the driver voltage is greater than half the battery voltage when the driver is on.
2. Fuel pump relay driver short circuit to ground, i.e. the driver voltage is less than one third of the battery voltage when the driver is off.
3. Fuel pump relay driver open circuit, i.e. the driver voltage is greater than one third of the battery voltage but less than two thirds of the battery
voltage when the driver is off.

 

jfall - glad you like the info, but what does your post refer to, a specific problem; a suggested test method for a specific problem, etc.? Did you mean to post here, or start your own so it could become a sticky?

 

Hi Savana

will these manuals give me the codes for a Series II td5 2003?

And can you tell me is the TD5 OBDII compliant? I am having heaps of trouble with the SLS and am wondering what my options are with gearing up to read the faults myself.

Look forward to hearing from you soon

 

2003 would be OBDII compliant. The files above are for the engine module only.

But there are multiple ECUs on the Discovery 2, and generic code readers only "talk" to the engine computer. The SLABS computer needs a more advanced scanner or dealer level computer to chit chat.

The D2 has the following modules on the OBDII "party line":

Engine ECU, ACE, SLABS, BCU, Airbag, cruise control, transmission, and fuel burning heater (not all modules on all models).

 

Just posting the Bosch manual in one piece

 

thanks

 

Thanks!