MDC Mitsubishi Diff Controller User Manual Copyright – MoTeC Pty Ltd – 2001-2007 The information in this document is subject to change without notice. While every effort is taken to ensure correctness, no responsibility will be taken for the consequences of any inaccuracies or omissions in this manual.
Contents Introduction .........................................................................1 MDC Functionality ..............................................................2 Mode selection ................................................................................................... 2 Lock Calculation................................................................................................. 2 Slip Control........................................................................................
MoTeC MDC 1 Introduction Introduction The MoTeC Mitsubishi Diff Controller (MDC) is a direct replacement for the Active Centre Diff (ACD) controller in the Mitsubishi EVO7 to EVO9. The MDC also supports centre diff control on Active Yaw Control (AYC) equipped vehicles. However the yaw control hardware is not used. EVO4 and EVO5 are not supported as the AYC module in these vehicles uses a slightly different connector. These vehicles could be rewired to suit the MDC, please contact MoTeC for details.
MoTeC MDC 2 Functionality MDC Functionality Mode selection There are six user selectable control modes, four of which are user configurable. The control modes can be cycled though using the dash mounted ACD button in the sequence below.
MoTeC MDC 3 Functionality The lock percentage for the constant lock mode is determined according to the following strategy: Constant lock % ABS OFF 5% Lock ON Handbrake OFF 0% Lock ON % lock The constant lock % is equivalent to the maximum lock achieved by the Mitsubishi factory AYC / ACD controller.
MoTeC MDC 4 Functionality Speed Measurement The four wheel speed sensors are either directly connected to the MDC, or via the ABS module (if fitted). If the ABS module is removed, the sensors must be directly connected to the MDC. The MDC wheel speed inputs can be configured as hall effect or magnetic sensors with adjustable thresholds, and individual sensors can be enabled or disabled. The speed calibration can be adjusted for different wheel sizes and sensor teeth.
MoTeC MDC 5 Functionality Note: if the MDC is powered up with the steering at full lock it will read +/-360deg when the wheels are straight. This is a characteristic of the steering sensor which will be automatically corrected when the vehicle starts moving, through analysis of steering angle, vehicle speed and lateral G force. Hydraulic Pressure Pump Control The MDC reads the hydraulic pressure sensor and controls the pump to maintain hydraulic pressure for the ACD.
MoTeC MDC 6 Functionality The ECU sends the calculated engine efficiency point (based on manifold pressure, throttle position, mass flow, etc) to the MDC. The MDC sends wheel speeds, longitudinal and lateral G, diff parameters and fault codes to the ECU. See Appendix D – ECU Communications for more information on configuring ECU communications. Miscellaneous functions Fault indication Faults are indicated by flashing the mode light on the dash.
MoTeC MDC 7 Setup MDC Manager The MDC Manager software is necessary to configure an MDC unit from a PC. A new MDC unit must be configured before its initial use. Computer requirements The MDC Manager software runs under Windows 95, 98, ME, NT4, 2000 or XP operating systems. The minimum recommended PC specification is a Pentium 90 with 16MB RAM and a parallel port or USB port.
MoTeC MDC 8 Setup If a cell in the braking table is left blank, the corresponding cell value from the Acceleration table is used. Cell values should only be entered into the Braking table where a different value is required from the Acceleration table. The Desired Slip table specifies the value above which additional diff lock will be applied, according to the slip control setup parameters. The Acceleration and Braking tables specify %lock in 0.5% units.
MoTeC MDC 9 Setup Magnetic Levels If magnetic wheel speed sensors are used, the sensor thresholds must be specified in the magnetic levels table. Thresholds are configured separately for front and rear sensors. Up to 11 ascending speeds can be specified in the table and linear interpolation is used between points.
MoTeC MDC 10 Setup Speed Axis Up to 11 values can be specified for the speed axis that is used in all of the user mode Braking and Acceleration tables. The axis values must be ascending and duplicate values are not allowed. Spacing between values is not fixed, allowing non linear axes. Throttle Axis or MAP Axis Up to 11 values can be specified for the throttle or ECU Efficiency axis that is used in all of the user mode tables.
MoTeC MDC 11 Appendices MDC Installation The factory AYC / ACD ecu is attached with two bolts to the side of the centre console underneath the dashboard. The MDC replaces the factory controller and should be securely attached in the same position using the factory bolts.
MoTeC MDC 12 Appendices Appendices Appendix A – Fault Codes The MDC fault flags included in the CAN diagnostics are sent as a bit field (16 bit) with the following faults: Bit 0 (0x0001 = 1) Bad Configuration (CRC failure) Bit 1 (0x0002 = 2) Short circuit pump output Bit 2 (0x0004 = 4) Hydraulic pressure sensor failure Bit 3 (0x0008 = 8) Pump run time fault (pump could not achieve min pressure threshold) The MDC diagnostic flags included in the CAN diagnostics are sent as a bit field (16 bit) wit
MoTeC MDC 13 Appendices Appendix B – MDC Pinout and Links MDC Connector Pinout 1 2 3 4 5 6 7 8 9 10 11 12 13 31 32 33 34 35 36 37 38 39 40 41 14 15 16 17 18 19 20 21 22 23 24 25 26 42 43 44 45 46 47 48 49 50 51 52 Plug C38 Plug C37 Pin Function Notes 1 ACD valve output Switched positive output 6 Front left speed sensor input Magnetic or Hall 7 Rear right speed sensor input Magnetic or Hall 8 Rear left speed sensor input Magnetic or Hall 9 Front right speed sensor input Mag
MoTeC MDC 14 Appendices Links The only user changeable link is the CAN TERM link on the component side of the MDC circuit board. This link may be soldered closed to place a 100ohm termination across the CAN bus.
MoTeC MDC 15 Appendices Appendix C – CAN Wiring Practices The CAN bus should consist of a twisted pair trunk with 100R (0.25Watt) terminating resistors at each end of the trunk. The preferred cable for the trunk is 100R Data Cable but twisted 22# Tefzel is acceptable. The maximum length of the bus is 16m (50ft) including the MoTeC CAN Cable (PC to CAN Bus Communications Cable) CAN Devices (such as MoTeC ADL, M800 etc) may be connected to the trunk with up to 500mm (20in) of twisted wire.
MoTeC MDC 16 Appendices Appendix D – ECU Communications The MDC can communicate with the MoTeC EVO89 or EVO48 OEM ECU using existing factory wiring. This functionality requires M800 ECU firmware V3.21D or later. ECU Link Configuration The links on the OEM adaptor board must be changed from the default settings to allow communication with the MDC.
MoTeC MDC 17 Appendices
MoTeC MDC 18 Appendices Receiving ECU Data If ECU/MDC communications has been enabled, the MDC receives ECU Efficiency point from the ECU. The ECU efficiency point (calculated from manifold pressure or throttle position) may be used as an input to the diff lock calculation by setting the Lock Table Axis to Manifold Pressure under File | Setup | User Modes in MDC Manager.
MoTeC MDC 19 Appendix E – CAN Messages The MDC communicates on a User CAN bus running at 1Mbit/s. MDC operational data messages are each transmitted at 50Hz. MDC diagnostic messages are each transmitted at 25Hz. 50Hz Messages CAN ID 0x1F4 Byte Bits 0 4..7 0..4 1 2 3 4 5 6 7 CAN ID 0x1F4 Byte Bits 0 4..7 0..4 1 2 3 4 5 6 7 CAN ID 0x1F4 Byte Bits 0 4..7 0..4 1 2 3 4 5 6 7 CAN ID 0x1F4 Byte Bits 0 4..7 0..
MoTeC MDC CAN ID 0x1F4 Byte Bits 0 4..7 0..4 1 2 3 4 5 6 7 CAN ID 0x1F4 Byte Bits 0 4..7 0..4 1 2 3 4 5 6 7 20 Data Compound Id = 4 Front Right Wheel Speed (0.1 km/h resolution) Front Left Wheel Speed (0.1 km/h resolution) Rear Right Wheel Speed (0.1 km/h resolution) Rear Left Wheel Speed (0.1 km/h resolution) Data Compound Id = 5 ABS Active Status (0 = Not Active, 1 = Active) Reserved Front Wheels Speed (0.1 km/h resolution) Rear Wheels Speed (0.
