Engine Control Module (ECM) 4.4L (Discovery 3)

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

ECM Block (engine control unit) accepts input signals from the following components and according to the following parameters:

• Fuel supply to the engine.
• Distribution of ignition timing.
• Fueling in a closed loop.
• Detonation control.
• Idle speed adjustment
• Reducing exhaust toxicity.
• On-board diagnostics.
• Providing an interface with the anti-theft system

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

• Throttle actuator
• Ignition coils (8 pieces)
• Oxygen sensor heaters (4 pieces)
• Nozzles (8 pieces)
• EGR stepper motor (exhaust gas recirculation)
• Variable valve timing valves (2)
• Purge valve
• Cooling system fan
• Fuel pump relay
• Starter relay
• Air Conditioner Condenser Fan Module
• EMS power relay
• Control of the viscous clutch of the cooling system fan
• Generator control
• Power steering
• Fuel Tank Leak Test Module (DMTL) (only for NAS standard vehicles)

C0634 ECM Connector Pinout Table

Contact No.	Purpose	Input signal/output signal
1	CAN (local area network controller)	Input signal/output signal
2	CAN (local area network controller)	Input signal/output signal
3	Determining the Generator Status	Input signal
4	UHEGO A-series weight	-
5	UHEGO B-series weight	-
6	Not used	-
7	Not used	-
8	Not used	-
9	Not used	-
10	Not used	-
11	CKP mass (crankshaft position)	-
12	Mass of row A of CMP sensor (crankshaft position)	-
13	Mass of row B of CMP sensor (crankshaft position)	-
14	UHEGO sensor signal for cylinder bank B	Input signal
15	Electronic throttle body weight	-
16	MAF mass (mass air flow)	-
17	HEGO mass	-
18	Not used	-
19	Knock Sensor Mass 1	-
20	Knock Sensor 2 Mass	-
21	Knock Sensor Mass 3	-
22	Knock Sensor Mass 4	-
23	5V power supply for electronic throttle body	Output signal
24	Fuel pump relay	Output signal
25	Not used	-
26	Not used	-
27	Not used	-
28	Not used	-
29	Radiator temperature sensor	Input signal
30	Engine start sensor signal	Input signal
31	Not used	-
32	Not used	-
33	CMP sensor signal (crankshaft position) series B	Input signal
34	CMP sensor signal (crankshaft position) row A	Input signal
35	Not used	-
36	UHEGO sensor signal row A	Input signal
37	Mass signal of UHEGO sensor row A	-
38	Mass signal of UHEGO sensor row B	-
39	Fuel temperature sensor	Input signal
40	Fuel pressure sensor	Input signal
41	Not used	Input signal
42	Not used	Input signal
43	Knock Sensor 1 +	Output signal
44	Knock Sensor 2 +	Output signal
45	Knock Sensor 3 +	Output signal
46	Knock Sensor 4+	Output signal
47	Generator control	Output signal
48	Fan of the control system mounting box	Output signal
49	Not used	-
50	EGR stepper motor (exhaust gas recirculation) 4	Output signal
51	EGR stepper motor (exhaust gas recirculation) 3	Output signal
52	EGR stepper motor (exhaust gas recirculation) 2	Output signal
53	EGR stepper motor (exhaust gas recirculation) 1	Output signal
54	Ignition coil cylinder 4 B	Output signal
55	Ignition coil cylinder 4A	Output signal
56	Ignition coil cylinder 3 B	Output signal
57	Not used	-
58	Not used	-
59	Not used	-
60	Not used	-
61	Not used	-
62	Not used	-
63	Not used	-
64	Not used	-
65	Not used	-
66	Not used	-
67	Not used	-
68	Not used	-
69	Not used	-
70	MAF (mass air flow)	Input signal
71	Purge valve	Output signal
72	- starter relay	-
73	Throttle body supply	Output signal
74	"-" direction of throttle rotation	Output signal
75	"+" direction of throttle rotation	Output signal
76	UHEGO A-row cylinder heater	Output signal
77	UHEGO B-row heater	Output signal
78	Cylinder injector 4B	Output signal
79	Cylinder injector 4A	Output signal
80	Cylinder injector 3B	Output signal
81	Cylinder injector 3A	Output signal
82	Cylinder 2B injector	Output signal
83	Cylinder injector 2A	Output signal
84	Cylinder 1B injector	Output signal
85	Cylinder injector 1A	Output signal
86	VVT row A	Output signal
87	VVT row B	Output signal
88	Viscous Clutch Fan Control	Output signal
89	Not used	-
90	Oil temperature sensor	Input signal
91	Throttle body control signal	Input signal
92	+ starter relay	Output signal
93	Not used	-
94	Request for regulation of the viscous clutch of the cooling system fan	Input signal
95	Purge valve	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 3	-
4	Power Mass 2	-
5	ECM Power Supply (engine control unit)	Input signal
6	APP sensor mass (accelerator pedal position sensor) 1	-
7	APP sensor mass (accelerator pedal position sensor) 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 controller)	Output signal
19	Sensor Power 2 APP (accelerator pedal position sensor)	Output signal
20	Fuel pump control system	Output signal
21	Not used	-
22	Not used	-
23	Not used	-
24	APP sensor signal (accelerator pedal position sensor) 1	Output signal
25	Not used	-
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 controller)	Input signal
32	Sensor Power 1 APP (accelerator pedal position sensor)	Output signal
33	DMTL	Output signal
34	Not used	-
35	- speed switch	Output signal
36	+ speed switch	Input signal