Engine Control Module (ECM) 4.0L (Discovery 3)

ECM (engine control unit) is located in the mounting box in the engine compartment chamber on the passenger side, fixed to the partition.

Incoming signals

To the ECM input (engine control unit) the following signals are received:

• Central switching unit
• Coolant temperature
• Brake switch
• Manifold Absolute Pressure
• Accelerator pedal position 1
• Accelerator pedal position 2
• Throttle position 1
• Throttle position 2
• Engine cooling fan speed
• Engine Crankshaft Position and Speed Sensor (crankshaft sensor)
• Camshaft Position Sensor
• Engine oil temperature
• IAT sensor (intake air temperature) (built into MAF (mass air flow))
• MAF (mass air flow)
• Knock Sensors (2)
• Cruise control speed switches (resistive multi-link chains)
• Oxygen sensors (4)
• Vehicle speed (via CAN bus) (local area network of controllers))
• Differential pressure eGr (exhaust gas recirculation)
• EGR (exhaust gas recirculation) mAp (manifold absolute pressure)
• Generator control circuits

Output signals

ECM Block (engine control unit) generates output signals to control the following components and parameters:

• Throttle actuator
• Ignition coils (6)
• Oxygen Sensor Heaters (4)
• Fuel injectors (6)
• EGR valve (exhaust gas recirculation)
• IMT valve (intake manifold adjustments)
• Purge valve
• Fuel pump relay
• Starter relay
• Air Conditioner Condenser Fan Module (CAN) (local area network of controllers))
• EMS power relay
• Control of the viscous clutch of the cooling system fan
• Generator control

ECM Block (engine control unit) controls the phased supply of fuel to all engine cylinders. The engine uses an ignition system with separate ignition coils (6 coils), which are installed directly on the spark plugs. In order to maintain optimal engine operation, the ECM (engine control unit) detects detonation in each individual cylinder and suppresses it by adjusting the ignition timing in each cylinder.

ECM Management Strategy (engine control unit) is based on the torque demanded by the driver and the various ECUs in the vehicle. The EMS uses various sensors to determine the torque that should be produced by the engine. These include:

• Mass Air Flow Sensor
• Accelerator pedal position sensor
• Engine temperature sensors
• Oxygen sensors

The EMS processes these signals and decides on the amount of torque to be generated. Torque is created by various actuators that supply air, fuel and sparks to the engine. (electronic throttle, injectors, coils, etc.). EMS also via CAN bus (local area network of controllers) communicates with other ECUs in the vehicle to obtain additional data. This includes:

• ABS control unit (anti-lock braking system)
• TCM (transmission control unit)
• Transfer case controller

Contact No.	Purpose	Input signal/output signal
1	CAN (local area network of controllers)	Input signal/output signal
2	CAN (local area network of controllers)	Input signal/output signal
3	Determining the Generator Status	Input signal
4	UHEGO A-series weight	-
5	UHEGO B-series weight	-
6	- engine start sensor	Input signal
7	Camshaft sensor mass	-
8	Not used	-
9	Not used	-
10	Sensor mass 3	-
11	Sensor mass 4	-
12	Sensor mass 5	-
13	Not used	-
14	Reserve mass	-
15	Sensor mass 6	-
16	Not used	-
17	Not used	-
18	MAF mass (mass air flow)	-
19	Knock Sensor Mass Row A	-
20	Knock Sensor Mass Row B	-
21	Not used	-
22	Not used	-
23	Oil temperature sensor	Input signal
24	Sensor power supply 6	Output signal
25	LIN A	Output signal
26	UHEGO series B (+)	Input signal
27	UHEGO series B (-)	-
28	UHEGO series A (+)	+
29	UHEGO series A (-)	-
30	+ engine start sensor	Input signal
31	Not used	-
32	Not used	-
33	Not used	-
34	CMP sensor signal (camshaft position) row A	Input signal
35	Not used	-
36	Not used	-
37	Not used	-
38	Differential pressure sensor	Input signal
39	Not used	-
40	Fuel pressure sensor	Input signal
41	Not used	-
42	Knock sensor row A (+)	Input signal
43	Knock sensor row B (+)	Input signal
44	Not used	-
45	Not used	-
46	Fuel temperature sensor	Input signal
47	Sensor power supply 5	Output signal
48	Sensor power supply 4	Output signal
49	Not used	-
50	Not used	-
51	Not used	-
52	Not used	-
53	Not used	-
54	Not used	-
55	Not used	-
56	Ignition coil cylinder 3 B	Output signal
57	Ignition coil cylinder 3A	Output signal
58	Ignition coil cylinder 2 B	Output signal
59	Ignition coil cylinder 2 A	Output signal
60	Ignition coil cylinder 1 B	Output signal
61	Ignition coil cylinder 1 A	Output signal
62	Mass of ignition coil row A	-
63	Viscous Clutch Fan Control Circuit	Input signal
64	Ignition Coil Mass Row B	-
65	Throttle Position Sensor 1	-I
66	Air temperature sensor	Input signal
67	Throttle Position Sensor 2	Input signal
68	Coolant temperature sensor	Input signal
69	MAP (manifold absolute pressure)	Input signal
70	MAF (mass air flow)	Input signal
71	Not used	-
72	Sensor power supply 3	Output signal
73	Not used	-
74	throttle rotation direction (-)	Output signal
75	throttle direction (+)	Output signal
76	UHEGO heater series A	Output signal
77	UHEGO heater series B	Output signal
78	Cylinder 1 B injector	Output signal
79	Cylinder 1 B injector	Output signal
80	Cylinder 2 A injector	Output signal
81	Cylinder 2 B injector	Output signal
82	Cylinder injector 3A	Output signal
83	Cylinder 3 B injector	Output signal
84	Intake Manifold Regulating Valve 1	Output signal
85	Not used	-
86	Not used	Output signal
87	Not used	Output signal
88	Not used	Output signal
89	Not used	-
90	EGR (exhaust gas recirculation)	Input signal
91	Not used	-
92	Purge valve	Output signal
93	Request for regulation of the viscous clutch of the cooling system fan	Output signal
94	Not used	-
95	Fuel pump relay	Output signal
96	Generator control	Output signal

C0635 ECM Connector Pinout Table

Contact No.	Purpose	Input signal/output signal
1	Signal mass 1	-
2	Power Mass 1	-
3	Power Mass 2	-
4	ECM Power Supply (engine control unit)	Input signal
5	Power Mass 3	-
6	APP sensor mass (accelerator pedal position) 1	-
7	APP sensor mass (accelerator pedal position) 2	-
8	Not used	-
9	Not used	-
10	Not used	-
11	Not used	-
12	Parking/Neutral Position Signal	Input signal
13	Not used	-
14	Not used	-
15	Not used	-
16	EMS relay	Output signal
17	Crankshaft cranking request	Output signal
18	+ CAN buses (local area network of controllers)	Output signal
19	Sensor Power 2 APP (accelerator pedal position)	Output signal
20	Fuel pump control	Output signal
21	Not used	-
22	Not used	-
23	Not used	-
24	APP sensor signal (accelerator pedal position) 1	Output signal
25
26	Brake light switch	Input signal
27	Not used	-
28	Not used	-
29	Not used	-
30	Ignition switch	Input signal
31	+ CAN buses (local area network of controllers)	Input signal
32	Sensor Power 1 APP (accelerator pedal position)	Output signal
33	DMTL	Output signal
34	Not used	-
35	- speed switch	Output signal

Electronically controlled throttle

The V6 engine's torque is controlled by the throttle body, which is located on the intake manifold in the engine bay. APP sensor (accelerator pedal position) detects the driver's command to change the throttle position. This signal is input to the ECM, and the throttle valve opens by means of an electric motor built into the throttle body, changing its angle. A sensor in the throttle body determines the position of the valve and the rate of change of its angle of rotation. The ECM software (engine control unit) provides for calibration of the valve position in each ignition cycle. When the ignition is turned on (oN position), ECM (engine control unit) fully opens and closes the throttle valve, thereby performing self-diagnosis and calibration. The throttle body is connected to the ECM to reduce electrical noise (engine control unit) using a pair of twisted wires. For more information, refer to Acceleration Control (310-02A)

Throttle Body Connector Pinout Table C0175

Contact No.	Purpose	Input signal/output signal
1	Signal 1	Output signal
2	Power supply 5V	Input signal
3	Signal 2	Output signal
4	Weight	-
5	+ drives	Input signal
6	- drives	-

(The original text can be found at: «LRman.ru»)