Signal Description Motronic 4.4
WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.
Connector A #A1 - #A43
All the values specified below are measured between the terminal specified in column 1 and terminal #A42 (signal ground), unless otherwise indicated in brackets.
NOTE:
It is important that the breakout box is connected and that the ground terminals have been checked before readings are taken. See Connecting the breakout box.
The values specified in the table apply with the engine unloaded and at normal operating temperature.
| U= | DC voltage in volts (V) | UAC = | AC voltage in volts (V) |
| Ubat = | battery voltage | f = | frequency in Hertz (Hz) |
| Ulow = | voltage approximately 0 V or 0 V | % duty = | duty cycle (pulse ratio) as a percentage (%) |
| t = | time in milliseconds (ms) | - | - |
| Terminal | Signal type | Ignition on | Idling speed | Other |
|---|---|---|---|---|
| #A1 | - | - | - | - |
| #A2 | Signal (+) front knock sensor (KS) (measured to terminal #A17) |
Ulow | - | - |
| #A3 | Power ground mass air flow (MAF) sensor |
Ulow | - | - |
| #A4 | Signal mass air flow (MAF) sensor (measured to terminal #A5) |
U = 0.1 - 0.2 V | U ≈ 0.9 V | U increases with increasing air mass |
| #A5 | Signal ground mass air flow (MAF) sensor |
Ulow | - | - |
| #A6 | Signal ground engine speed (RPM) sensor |
Ulow | - | - |
| #A7 | Control signal engine cooling fan (FC) low-speed |
Engine cooling fan (FC) off: Ubat Engine cooling fan (FC) on: U ≈ 0.1 V |
- | - |
| #A8 | - | - | - | - |
| #A9 | Control signal injector 5 |
U bat | t = 2.2 - 3.6 ms | t increases with engine speed (RPM) and load (measured with EVAP not active) |
| #A10 | Control signal injector 1 |
Ubat | t = 2.2 - 3.6 ms | t increases with engine speed (RPM) and load (measured with EVAP not active) |
| #A11 | Opening signal the idle air control (IAC) valve |
% duty ≈ 25% | % duty = 21 - 32% | % duty increases with load (measured with EVAP not active) |
| #A12 | 15- supply (power supply from the ignition switch) | U bat | - | - |
| #A13 | Power ground | Ulow | - | - |
| #A14 | Control signal front heated oxygen sensor (HO2S), preheating |
U bat | Preheating off: U ≈ Ubat Preheating on: U ≈ 0.4 V |
- |
| #A15 | Power supply the throttle position (TP) sensor |
U ≈ 4.8 V | - | - |
| #A16 | Signal the throttle position (TP) sensor |
U ≈ 0.5 V at closed throttle position (CTP) (idling) U ≈ 4.3 V at wide open throttle (WOT) |
- | - |
| #A17 | Signal (-) front and rear knock sensors (KS) |
U low | - | - |
| #A18 | Signal ground sensor (measured to the battery negative terminal) |
Ulow | - | - |
| #A19 | Signal (-) rear heated oxygen sensor (HO2S) |
U ≈ 0.7 V | Only measured with the ignition on | - |
| #A20 | Signal engine speed (RPM) sensor (measured to #A6) |
U low | U AC
≈ 1.6 V f = 825 Hz |
- |
| #A21 | Signal camshaft position (CMP) sensor |
U = Ulow
or 5.0 V U = Ulow or Ubat |
f ≈ 7 Hz | f increases with engine speed (RPM) |
| #A22 | Control signal engine cooling fan (FC) high-speed |
Engine cooling fan (FC) off: Ubat Engine cooling fan (FC) on: U < 0.3 V |
- | - |
| #A23 | Control signal injector 4 |
U bat | t = 2.2 - 3.6 ms | t increases with engine speed (RPM) and load (measured with EVAP not active) |
| #A24 | Control signal injector 3 |
U bat | t = 2.2 - 3.6 ms | t increases with engine speed (RPM) and load (measured with EVAP not active) |
| #A25 | Closing signal the idle air control (IAC) valve |
% duty = 75% | % duty = 68 -78% | % duty decreases with load (measured with EVAP not active) |
| #A26 | 30-supply (power supply from the battery) | U bat | - | - |
| #A27 | Power supply (from the main relay) | U bat | - | - |
| #A28 | Power ground control module |
U low | - | - |
| #A29 | Control signal rear heated oxygen sensor (HO2S), preheating |
U bat | Preheating off: U ≈ U bat Preheating on: U ≈ 0.4 V |
- |
| #A30 | Signal (+) rear knock sensor (KS) (measured to terminal #A17) |
U low | - | - |
| #A31 | Signal the engine coolant temperature (ECT) sensor |
(at an engine coolant temperature (ECT) of +46°C, the engine control module (ECM) changes the voltage range) | (+20°C) U ≈ 1.81 V (+30°C) U ≈ 1.34 V (+45°C) U ≈ 0.83 V (+46°C) U ≈ 4.0 V (+80°C) U ≈ 2.73 V (+100°C) U ≈ 1.96 V |
- |
| #A32 | Signal (+) front heated oxygen sensor (HO2S) |
U = 1.1 - 1.2 V (measured to terminal #A42) | U oscillates rapidly between 0.0-0.9 V when the probe is warm. Low voltage = lean engine High voltage = rich engine (measured to terminal #A33) |
- |
| #A33 | Signal (-) front heated oxygen sensor (HO2S) |
U ≈ 0.7 V | Only measured with the ignition on | - |
| #A34 | Signal (+) rear heated oxygen sensor (HO2S) |
U low (measured to terminal #A42) | U at even load approximately 0.6 V can vary between 0.0 - 0.9 V depending on the operating conditions (measured to terminal #A19) |
- |
| #A35 | Outer temperature sensor | U ≈ 4.9 V | - | - |
| #A36 | Power supply camshaft position (CMP) sensor |
U ≈ Ubat | - | - |
| #A37 | Pulsed secondary air injection system (PAIR) pump valve, control signal | U bat | pulsed secondary air injection system (PAIR) pump valve not active ≈ U bat | active ≈ U low |
| #A38 | Control signal injector 2 |
U bat | t ≈ 2.2 - 3.6 ms | t increases with engine speed (RPM) and load (measured with EVAP not active) |
| #A39 | Control signal Canister purge (CP) valve |
U bat | Canister purge (CP) valve: % duty = 0 - 33% |
- |
| #A40 | - | - | - | - |
| #A41 | Control signal main relay |
U ≈ 1 V | - | - |
| #A42 | Signal ground control module (measured to the battery negative terminal) |
U low | - | - |
| #A43 | - | - | - | - |
Connector B terminals #B1 - #B43
All the values specified below are measured between the terminal specified in column 1 and terminal #B28 (signal ground), unless otherwise indicated in brackets in column 2.
NOTE:
It is important that the breakout box is connected and that the ground terminals have been checked before readings are taken. See Connecting the breakout box.
The values specified in the table apply with the engine unloaded and at normal operating temperature.
| U= | DC voltage in volts (V) | UAC = | AC voltage in volts (V) |
| Ubat = | battery voltage | f = | frequency in Hertz (Hz) |
| Ulow = | voltage approximately 0 V or 0 V | % duty = | duty cycle (pulse ratio) as a percentage (%) |
| t = | time in milliseconds (ms) | * | Multimeter 951-0060 reads approximately 71 Hz due to interference in the signal. |
| Terminal | Signal type | Ignition on | Idling speed | Other |
|---|---|---|---|---|
| #B1 | Power supply accelerometer |
U ≈ 5.0 V | - | - |
| #B2 | Signal torque limiting (from automatic transmission) |
U ≈ 1- 2 V below Ubat | - | U low on ignition retardation request (retardation levels 2 and 3) |
| #B3 | Signal torque limiting (from automatic transmission) |
U ≈ 1- 2 V below Ubat | - | Ulow on ignition retardation request (retardation levels 1 and 3) |
| #B4 | Signal torque limiting acknowledgment (to automatic transmission) |
U ≈ 2.0 V below Ubat | - | Ulow when the request has been received |
| #B5 | - | - | - | - |
| #B6 | Signal air conditioning (A/C) compressor status |
Ulow | A/C compressor off: U < 0.1 V A/C compressor on: U ≈ Ubat |
- |
| #B7 | Control signal malfunction indicator lamp (MIL) (to the combined instrument panel) |
Lamp lit: U ≈ 0.8 V Lamp not lit: Ubat |
- | - |
| #B8 | - | - | - | - |
| #B9 | Signal A/C pressure sensor |
U ≈ 0.9 V | U ≈ 0.9 V (when the air conditioning has not been connected) U increases with air conditioning (A/C) pressure |
- |
| #B10 | - | - | - | - |
| #B11 | Control signal ignition discharge module (IDM) |
U ≈ 0.1 V | f ≈ 35 Hz* | U and f increase with engine speed |
| #B12 | Signal load Tq (to automatic transmission) |
U ≈ 0.8 V | f ≈ 35 Hz | f increases with engine speed (RPM) |
| #B13 | - | - | - | - |
| #B14 | - | - | - | - |
| #B15 | Power supply fuel tank pressure sensor |
U ≈ 5 V | - | - |
| #B16 | - | - | - | - |
| #B17 | - | - | - | - |
| #B18 | Signal speed (from combined instrument panel) |
U ≈ Ulow
or Ubat (the voltage depends on the position of the front wheels) |
- | f increases with speed f = 40 Hz at 20 km/h. |
| #B19 | Control signal fuel pump |
U ≈ Ubat | Closed U ≈ Ulow |
- |
| #B20 | Signal throttle position (TP) sensor (to automatic transmission) |
U ≈ 0.5 V at closed throttle position (CTP) (idling) U ≈ 4.3 V at wide open throttle (WOT) |
- | - |
| #B21 | Signal tachometer (to combined instrument panel) |
U ≈ Ubat | f ≈ 28 Hz | f increases with engine speed (RPM) |
| #B22 | Atmospheric pressure sensor | U ≈ 4.6 V | - | - |
| #B23 | Signal engine coolant temperature (ECT) (to ECC and combined instrument panel) |
Cold engine (+20°C): f ≈ 40 Hz Engine at operating temperature (+100°C): f ≈ 21 Hz |
- | - |
| #B24 | Signal constant idle speed compensation P/N position (from automatic transmission) |
P/N-position: U ≈ Ubat Other positions: U ≈ Ulow Manual: U ≈ 9.0 V |
- | - |
| #B25 | Signal air conditioning (A/C) relay status |
Ulow | Air conditioning (A/C) relay not activated: U < 0.1 V Air conditioning (A/C) relay activated: U ≈ Ubat |
- |
| #B26 | Signal malfunction indicator lamp (MIL) request (from automatic transmission) |
U ≈ 0 - 1 V | U ≈ Ubat NOTE! Other values apply if there are diagnostic trouble codes (DTCs) stored in the transmission control module (TCM). |
- |
| #B27 | Control signal fuel pump |
U ≈ 7.5 V | f = 42 Hz (multimeter set to UAC ) | - |
| #B28 | Signal ground sensor (measured to the battery negative terminal) |
U < 0.1 V | - | - |
| #B29 | Power supply A/C pressure sensor |
U ≈ 5.0 V | - | - |
| #B30 | - | - | - | - |
| #B31 | Fuel tank pressure sensor (certain markets only) | U max
≈ 4.7 V U nominal ≈ 2.5 V U min ≈ 0.6 V |
- | - |
| #B32 | Signal accelerometer |
U ≈ 2.5 V | - | - |
| #B33 | - | - | - | - |
| #B34 | - | - | - | - |
| #B35 | - | - | - | - |
| #B36 | Diagnostic lead K-link | U ≈ 1 - 2 V below Ubat | Other values apply if a generic fault-tracing instrument is connected to the data link connector (DLC) | - |
| #B37 | - | - | - | - |
| #B38 | Control signal pulsed secondary air injection system (PAIR) pump relay |
U ≈ Ubat | pulsed secondary air injection system (PAIR) pump valve off U ≈ Ubat | pulsed secondary air injection system (PAIR) pump valve active U ≈ Ulow |
| #B39 | Signal fuel consumption (to the trip computer) |
U ≈ 2 V below Ubat No trip computer: U ≈ Ubat |
f ≈ 14 - 25 Hz | f increases with engine speed (RPM) and load (measured with EVAP not active) |
| #B40 | Control signal air conditioning (A/C) relay (allows A/C to start) |
U ≈ 9 V | Air conditioning (A/C) permitted: Ulow air conditioning (A/C) not permitted: U ≈ 11 V |
- |
| #B41 | Control signal, turbocharger (TC) control valve | Ubat | - | Voltage decreases with increased valve synchronization. |
| #B42 | Turbocharger (TC) boost pressure limiting signal (from automatic transmission) | U ≈ 10 V | - | - |
| #B43 | - | - | - | - |