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Signal specification

HINT: All the values given below are measured between the relevant terminal in column 1 and terminal #3, unless otherwise indicated in brackets. 

HINT: The values specified in the table apply with the engine unloaded and at normal operating temperature. 

NOTE:

It is important that the breakout box is connected according to Connecting the breakout box. EMS 2000 , before the readings are taken.

Fig 1: Identifying EMS2000
GLL111998Courtesy of VOLVO CARS OF NORTH AMERICA.
U = DC voltage in volts (V) UAC = AC voltage in volts (V)
Ubat = Battery voltage f = Frequency in Hertz (Hz)
Ulow = Voltage near 0 V or 0 V % Pulse ratio Duty cycle (pulse ratio) as a percentage (%)
t = Cyclic time in milliseconds (ms)
Terminal 
(Engine control module (ECM) 
Breakout box) 
Signal type  Ignition on  Engine idling  Notes 
1/A1 Ignition coil cyl. 2/3 Control signal Ubat (for 1 second after the ignition is switched on) Low pulse for 3 milliseconds from Ubat to Ulow , then a voltage peak greater than or equal to 100 V Frequency 13 Hz when the engine is idling
2/A2 - - - -
3/A3 Power ground terminal #4 Ulow - -
4/A4 Canister purge (CP) valve, control signal Ubat for 1 second after the ignition is switched on - During control: the voltage oscillates between Ulow and Ubat
5/A5 Turbocharger (TC) control valve, control signal Ubat (for 1 second after the ignition is switched on) Ubat During control, a pulsed signal between Ubat and Ulow with a fixed frequency of 32 Hz and variable pulse ratio (% duty)
6/A6 - - - -
7/A7 - - - -
8/A8 Engine cooling fan (FC) high-speed, control signal Engine cooling fan (FC) off = Ubat
Engine cooling fan (FC) on = Ulow
- -
9/A9 - - - -
10/A10 System relay, control signal Ulow (after 1 second Ubat ) Ulow -
11/A11 Engine coolant temperature (ECT) sensor signal to the combined instrument panel f = 45 Hz at +25 °C
f = 20 Hz at +100 °C
- A pulsed signal between 0 V and 5 V with variable frequency and fixed pulse ratio (% duty)
f increases with decreasing temperature
12/A12 - - - -
13/A13 Boost pressure sensor 2, signal U = 1.8 V U = 0.7 V The voltage increases with increased pressure in the intake manifold.
14/A14 Air conditioning (A/C) system pressure sensor, signal U = 0.9 V U = 0.9 V (when the air conditioning (A/C) has not been on) The voltage depends on the pressure in the system
1.4-1.8 V when the air conditioning (A/C) is activated
15/A15 Mass air flow (MAF) sensor, ground Ulow - -
16/B1 Mass air flow (MAF) sensor, signal Ulow U = 0.6 V U increases with engine speed (RPM) and load
17/B2 - - - -
18/B3 Atmospheric pressure sensor, signal (model year -00) U = 4.6 V U = 4.6 V The voltage varies with the atmospheric pressure
19/B4 Knock sensor (KS) ground screen Ulow - -
20/B5 Torque limiting signal from DSA to ECM U = 5 V U = 2 V (with DSA)
U = 5 V (without DSA)
Pulsed signal with fixed frequency of 200 Hz and fixed pulse ratio of 3 ms pulse with factor Tr = 0
21/B6 - - - -
22/B7 - - - -
23/B8 - - - -
24/B9 Engine speed (RPM) sensor, signal (-) U = 1.8 V U DC = 1.8 V
U AC = 2.5 Vt-t
Sine signal retained over DC
Frequency and amplitude depend on engine speed (RPM)
25/B10 - - - -
26/B11 - - - -
27/B12 CAN-H to / from TCM U = 2-3 V average voltage U = 2-3 V average voltage -
28/B13 Power ground terminal #1
Measured to the battery negative terminal (-)
Ulow - -
29/B14 15 supply
(+12 V, when the ignition is on)
Ubat - -
30/B15 30 supply
(+12 V, battery voltage)
Ubat - -
31/A16 - - - -
32/A17 Ignition coil cylinder 1/4 control signal Ubat (for 1 second after the ignition is switched on) Low pulse for 3 milliseconds from Ubat to Ulow , then a voltage peak greater than or equal to 100 V Frequency 13 Hz when the engine is idling
33/A18 Power ground terminal #3
Measured to the battery negative terminal (-)
- - -
34/A19 Malfunction indicator lamp (MIL), control signal
(to the combined instrument panel)
Ulow = lamp lit
Ubat = Lamp not lit
- -
35/A20 The leak diagnostic pump valve, control signal (Certain markets only) Ulow Ulow During the leak diagnostic the voltage oscillates between Ulow and Ubat
36/A21 Throttle position (TP) sensor output signal from ECM to DSA pulse ratio = 5%
(closed throttle position (CTP))
pulse ratio = 80%
(open)
pulse ratio = 5%
(closed)
pulse ratio = 80%
(open)
f = 50 Hz
A pulsed signal between 0 V and 9 V with fixed frequency and variable pulse ratio (% duty)
37/A22 - - - -
38/A23 Engine cooling fan (FC) low-speed, control signal Engine cooling fan (FC) off: Ubat
Engine cooling fan (FC) on =
- -
39/A24 - - - -
40/A25 Fuel consumption signal to the combined instrument panel. With infocenter: Ustable
Without infocenter: Ulow
Pulse train at 500 ms intervals; 1-10 x 1 ms pulses depending on engine coolant temperature (ECT), engine speed (RPM) and load. Pulses between 0 V and 5 V. -
41/A26 The leak diagnostic pump, signal (Certain markets only) Ulow - During the leak diagnostic the voltage oscillates between Ulow and Ubat
42/A27 - - - -
43/A28 Throttle position (TP) sensor, signal U = 0.6-0.7 V with unaffected throttle position (TP) sensor - U = 0.6-4.5 V depending on the position of the accelerator pedal (AP)
44/A29 Rear heated oxygen sensor (HO2S) signal measured to terminal #75 U = 0.5 V U = oscillates between 0.1 V - 1 V, cold three-way catalytic converter (TWC).
U = fixed value 0.4 V - 0.6 V, hot three-way catalytic converter (TWC).
-
45/A30 Front heated oxygen sensor (HO2S) signal measured to terminal #75 U = 0.5 V The voltage fluctuates between 0 - 1 V High voltage = Rich
Low voltage = Lean
46/B16 - - - -
47/B17 Engine coolant temperature (ECT) sensor, signal Uaverage = 2.6 V (+25 °C)
Uaverage = 0.6 V (+100 °C)
Uaverage = 2.6 V (+25 °C)
Uaverage = 0.6 V (+100 °C)
Voltage decreases with increasing temperature
48/B18 Intake air temperature (IAT) sensor, signal
intake air
U = 2 V at +25 °C
U = 0.25 V at +100 °C
- -
49/B19 - - - -
50/B20 - - - -
51/B21 Knock sensor (KS), signal Ulow - -
52/B22 Speed signal from the ABS control module Ubat Ubat (-1 V) Pulsed signal between Ulow and Ubat when the front left wheel is rotated
53/B23 - - - -
54/B24 Engine speed (RPM) sensor, signal (+)
Measured to terminal #24
Ulow UAC = 5 Vt-t
f = 775 Hz
(current RPM)
DC 1.8 Volts with
retained sine signal
amplitude and frequency increase with engine speed
55/B25 - - - -
56/B26 Immobilizer communication cable (also data link connector (DLC) communication link) No communication on the cable: U = 90% of Ubat.
During communication: data communication, pulsed signal between Ubat and 0 V.
Other values apply if a generic fault-tracing instrument is connected to the data link connector (DLC). The engine control module (ECM) and immobilizer control module communicate with each other for 2 seconds after the ignition is switched on to determine whether engine start should be permitted. After this interval, the immobilizer switches internally so that the cable is connected to the communication link in the data link connector (#7).
57/B27 CAN-L to / from TCM U = 2-3 V average voltage U = 2-3 V average voltage -
58/B28 Camshaft position (CMP) sensor, signal U = 0 V or 5 V depending on position of the camshaft - Variable pulse ratio at constant engine speed due to the design of the camshaft position (CMP) sensor.
59/B29 Injector 1, control signal Ubat t = approximately 2 ms Pulsed signal from Ubat to Ulow , then a voltage peak of 60 V. The pulse length varies with engine speed (RPM) and load
60/B30 Injector 3, control signal Ubat t = approximately 2 ms Pulsed signal from Ubat to Ulow , then a voltage peak of 60 V. The pulse length varies with engine speed (RPM) and load
61/A31 - - - -
62/A32 Camshaft reset valve, control signal Ubat for 1 second after the ignition is switched on f = 250 Hz A pulsed signal with fixed duty cycle and variable frequency.
63/A33 Front heated oxygen sensor (HO2S), preheating, control signal U = 0 V
Ubat when the system relay is connected
Preheating off: Ubat
Preheating on: U = 0.5-4.5 V
Pulsed signal from Ubat to Ulow . The pulse ratio reduces as the temperature in the heated oxygen sensor (HO2S) increases
64/A34 Idle air control (IAC) valve, control signal Ubat for 1 second after the ignition is switched on Ulow A pulsed signal with fixed duty cycle and variable frequency.
65/A35 Rear heated oxygen sensor (HO2S), preheating, control signal U = 0 V
Ubat when the system relay is connected
Preheating off: Ubat
Preheating on: U = 0.5-4.5 V
Pulsed signal from Ubat to Ulow . The pulse ratio reduces as the temperature in the heated oxygen sensor (HO2S) increases
66/A36 Power supply from the system relay Ubat
(for 1 second after the ignition is switched on)
Ubat -
67/A37 Power ground terminal #2
Measured to the battery negative terminal (-)
Ulow - -
68/A38 A/C relay, control signal Ubat Ubat when the relay is not connected
Ulow when the relay is connected
-
69/A39 A/C fan, control signal Ulow bat when the engine cooling fan (FC) is running
Ulow when the engine cooling fan (FC) is not running
-
70/A40 Engine speed (RPM) signal to the combined instrument panel Ulow f = 25 Hz
(current rpm/30)
Pulsed signal between 0 V and 10 V with variable frequency and fixed pulse ratio (% duty)
71/A41 Torque signal from ECM to DSA Ulow No pulses when the engine is idling Pulsed signal between 0 V and Ubat with a length of up to 100 μseconds during throttle opening and engine without load
72/A42 Boost pressure sensor 1, signal (applies to model year 2001-) U = 1.8 V U = 1.8 V -
73/A43 Sensor, ground Ulow Ulow -
74/A44 Power supply, sensor U = 5 V U = 5 V Boost pressure sensor, boost pressure sensor 2, air conditioning (A/C) pressure sensor
75/A45 Front + rear heated oxygen sensor (HO2S), ground - - -
76/B31 Knock sensor (KS) ground Ulow - -
77/B32 Sensor, ground Ulow Ulow -
78/B33 Power supply, throttle position (TP) sensor U = 5 V U = 5 V -
79/B34 Sensor, ground Ulow Ulow Intake air temperature (IAT) sensor, boost pressure sensor 2, air conditioning (A/C) pressure sensor
80/B35 - - - -
81/B36 - - - -
82/B37 - - - -
83/B38 Power supply, camshaft position (CMP) sensor U = 5 V - -
84/B39 - - - -
85/B40 - - - -
86/B41     - -
87/B42 - - - -
88/B43 Air conditioning (A/C) request from MCC or ECC Ulow Air conditioning (A/C) relay not activated: Ulow
Air conditioning (A/C) relay activated: Ubat
Applies when the air conditioning (A/C) and blower fan switch buttons are in the on position
89/B44 Injector 4, control signal Ubat t = approximately 2 ms Pulsed signal from Ubat to Ulow , then a voltage peak of 60 V. The pulse length varies with engine speed (RPM) and load
90/B45 Injector 2, control signal Ubat t = approximately 2 ms Pulsed signal from Ubat to Ulow , then a voltage peak of 60 V. The pulse length varies with engine speed (RPM) and load