Signal specification, brake control module (BCM) with DSTC (dynamic stability and traction control)
All values given are between the relevant terminal in column 1 and terminal #A16 or #A47 (ground), unless otherwise indicated in brackets.
Connections 9, 13, 24, 26, 35, 38, 40-41 and 44 are not used.
NOTE:
It is important that the breakout box is connected and that the ground connections have been checked before starting to measure.
| U = | DC voltage in volts (V) | Ubat = | battery voltage (V) | ||
| I = | current in amperes (A) | Ulow = | voltage approximately 0 V | ||
| F = | Frequency in Hertz (Hz) |
| Breakout box terminal | Terminal ECU | Signal type | Ignition on | Miscellaneous |
| #A1 | #1 | 30-supply pump motor (power supply from battery) | U = Ubat | With a 30 A fuse. |
| #A2 | #2 | Diagnostic lead C-link | - | - |
| #A3 | #3 | Pedal position sensor, signal | 0 - 5 V | Brake pedal position, analog signal. 0 mm: ≈ 0 V 38.5 mm: ≈ 95% of 5 V |
| #A4 | #4 | 15-supply (power supply from the ignition switch) | U = Ubat | - |
| #A5 | #5 | Pedal position sensor, signal ground | U = Ulow | - |
| #A6 | #6 | Active yaw control sensor, power supply | U = Ubat | The active yaw control sensor receives 12 V from the control module. |
| #A7 | #7 | Pedal position sensor, power supply | U = 5 V | The pedal position sensor receives 5 V from the control module. |
| #A8 | #8 | Wheel sensor right rear, signal output. | Tooth at sensor U ≈ Ulow Cover at sensor U ≈ Ubat |
Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #8. Connect a voltmeter between #8 and ground connection #16. Turn the wheel slowly. |
| #A9 | #9 | - | - | - |
| #A10 | #10 | Wheel sensor left rear, signal output. | Tooth at sensor U ≈ Ulow Cover at sensor U ≈ Ubat |
Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #10. Connect a voltmeter between #10 and ground connection #16. Turn the wheel slowly. |
| #A11 | #11 | Control modules communication cable (CAN H) | U = 2 - 3 V | - |
| #A12 | #12 | Wheel sensor right front, signal output. | Tooth at sensor U ≈ Ulow Cover at sensor U ≈ Ubat |
Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #12. Connect a voltmeter between #12 and ground connection #16. Turn the wheel slowly. |
| #A13 | #13 | - | - | - |
| #A14 | #14 | Wheel sensor left front, signal output. | Tooth at sensor U ≈ Ulow Cover at sensor U ≈ Ubat |
Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #14. Connect a voltmeter between #14 and ground connection #16. Turn the wheel slowly. |
| #A15 | #15 | Control modules communication cable (CAN L) | U = 2 - 3 V | - |
| #A16 | #16 | Power and signal ground | U = Ulow | Ground terminal for the input and outlet valves and signal to the control module. |
| #A17 | #17 | Pressure build-up valve, power supply. | U = 4.75 - 5.25 V | - |
| #A18 | #18 | Brake pressure sensor 2 (B), voltage-feed | U = 4.75 - 5.25 V | Due to possibility of incorrect installation, #18-#20 may also be Brake pressure sensor 1 (A). |
| #A19 | #19 | Brake pressure sensor 2 (B), signal ground | U = Ulow | - |
| #A20 | #20 | Brake pressure sensor 2 (B), signal | U = 0.25 - 4.75 V | Analog signal 0 - 170 bar 23 mV/bar 0 bar = 0.5 V |
| #A21 | #21 | Brake pressure sensor 1 (A), signal ground. | U = Ulow | Due to possibility of incorrect installation, #21-#23 may also be Brake pressure sensor 2 (B). |
| #A22 | #22 | Brake pressure sensor 1 (A), voltage-feed. | U = 4.75 - 5.25 V | - |
| #A23 | #23 | Brake pressure sensor 1 (A), signal | U = 0.25 - 4.75 V | Analog signal 0 - 170 bar 23 mV/bar 0 bar = 0.5 V |
| #A24 | #24 | - | - | - |
| #A25 | #25 | Active yaw control sensor, communication cable (CAN L) | U = 2 - 3 V | - |
| #A26 | #26 | - | - | - |
| #A27 | #27 | Pedal pressure switch, signal | Open: U ≈ Ulow Closed: U ≈ Ubat |
The pedal pressure switch is open when the brake pedal is depressed. |
| #A28 | #28 | Test signal for the pedal pressure switch | - | - |
| #A29 | #29 | Active yaw control sensor, communication cable (CAN H) | U = 2 - 3 V | - |
| #A30 | #30 | Pedal pressure switch, signal | The pedal pressure switch is closed when the brake pedal is not pressed. | |
| #A31 | #31 | Pressure build-up valve, power supply | 12 V | Pulse width modulated signal: maximum 4A 18kHz |
| #A32 | #32 | 30-supply for the valves (power supply from battery) | U = Ubat | With a 30 A fuse. |
| #A33 | #33 | Front right wheel sensor. signal | Tooth against sensor: I ≈ 14 mA Cover against sensor: I ≈ 7 mA |
The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #12 |
| #A34 | #34 | Front right wheel sensor, power supply. | U = Ubat | The wheel sensor receives 12 V from the control module. |
| #A35 | #35 | - | - | - |
| #A36 | #36 | Rear left wheel sensor, power supply. | U = Ubat | The wheel sensor receives 12 V from the control module. |
| #A37 | #37 | Rear left wheel sensor, signal | Tooth against sensor: I ≈ 14 mA Cover against sensor: I ≈ 7 mA |
The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #10 in the chart |
| #A38 | #38 | - | - | - |
| #A39 | #39 | Active yaw control sensor, ground | U = Ulow | - |
| #A40 | #40 | - | - | - |
| #A41 | #41 | - | - | - |
| #A42 | #42 | Rear right wheel sensor, signal | Tooth against sensor: I ≈ 14 mA Cover against sensor: I ≈ 7 mA |
The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #8 in the chart |
| #A43 | #43 | Right rear wheel sensor, power supply | U = Ubat | The wheel sensor receives 12 V from the control module. |
| #A44 | #44 | - | - | - |
| #A45 | #45 | Front left wheel sensor, power supply | U = Ubat | The wheel sensor receives 12 V from the control module. |
| #A46 | #46 | Front left wheel sensor, signal | Tooth against sensor: I ≈ 14 mA Cover against sensor: I ≈ 7 mA |
The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #14 in the chart |
| #A47 | #47 | Power and signal ground | U = Ulow | Ground terminal for the pump motor. |