Engine Management System: V8 Description & Operation - Discovery II
ENGINE MANAGEMENT SYSTEM - V8
18-2-12 DESCRIPTION AND OPERATION
Connector 4 (C0637): This connector contains 40 pins and facilitates use of TestBook via the Diagnostic connector.
Also contained in this connector is the Malfunction Indicator Lamp (MIL), this instrument panel lamp informs the driver
of concerns within the engine management system.
Pin out details connector C0637
Pin No.
Function
Signal type
Reading
1
Not used
-
-
2
Not used
-
-
3
Not used
-
-
4
Not used
-
-
5
Not used
-
-
6
Not used
-
-
7
Not used
-
-
8
Low fuel level
Input, signal
Active high
9
Fuel tank pressure sensor (NAS vehicles with
vacuum type, EVAP system leak detection
capability only)
Output, reference
5V
10
Not used
-
-
11
Not used
-
-
12
Analogue fuel level (NAS vehicles with positive
pressure type, EVAP system leak detection only)
Input, signal
0-5V
13
Not used
-
-
14
Fuel tank pressure sensor (NAS vehicles with
vacuum type, EVAP system leak detection
capability only)
Input, signal
Analogue 0-5V
15
Not used
-
-
16
ATC compressor request
Input, signal
Active low
17
Engine speed output
Output, signal
PWM 0-5V
18
Not used
-
-
19
Not used
-
-
20
Malfunction indicator lamp 'ON'
Output
Switched earth
21
Not used
-
-
22
Vehicle speed signal (VSS)
Input, signal
PWM 0-12V
23
Not used
-
-
24
Not used
-
-
25
Not used
-
-
26
Not used
-
-
27
Not used
-
-
28
Not used
-
-
29
ATC compressor relay
Output
Switched earth
30
Not used
-
-
31
Positive pressure type EVAP system heater (02MY
vehicles only)
Output, drive
Switched earth
32
Diagnostic connector K-line
Bi-directional
Serial 0-12V
33
Immobiliser serial W link
Input, signal
Serial 0-12V
34
Rough road signal
Input, signal
PWM 0-12V
35
Not used
-
-
36
CAN data bus 'high line'
Bi-directional
5-2.5V
37
CAN data bus 'low line'
Bi-directional
0-2.5V
38
ATC stand by
Input, signal
Active low
39
Not used
-
-
40
Not used
-
-