BURKHART ENGINEERING

SEQUENTIAL-MANUAL TRANSMISSION WIKI

Hydraulic unit
Hydraulic pump

Hydraulic pump

Solenoid valve

Magnetic valve Clutch

click here for the spare part
BURKHART ENGINEERING

ADDITIONAL INFORMATION

Electric motor

The 12V DC motor drives the hydraulic external gear pump of the hydraulic unit and is activated via the SMG relay as soon as the minimum limit value for the hydraulic pressure is reached. This, as well as the maximum pressure value for switching off the electric motor, is flexible and always dependent on the temperature of the hydraulic oil. The warmer the hydraulic temperature, the higher the cut-off pressure for the pump.

Electric motor
Electric motor

Pressure relief valve

The pressure relief valve is installed in the hydraulic unit and serves as a safety element for the entire system. Should the pressure rise to 100 bar due to a defect, the valve opens and connects the suction and pressure side of the hydraulic pump.

Pressure relief valve

Temperature sensor

An NTC temperature sensor is installed in the hydraulic unit to monitor the hydraulic temperature. (-30 °C -> 26114 Ω; 130 °C -> 89 Ω)

Temperature sensor

Pressure sensor

A pressure sensor is installed in the hydraulic unit to monitor the hydraulic pressure. (0.5 V -> 0 bar; 4.58 V -> 100 bar)

Pressure sensor

SMG-relay

The salmon-coloured relay in the control unit box is switched by the control SMGunit and controls the electric motor. The relay sticks over time and should be replaced.

Relay

Hydraulic pump

The permanently installed pump is an external gear pump, which is driven by the 12V electric motor and thus builds up the required system pressure.

Hydraulic pump
Hydraulic pump

Pressure storage

The piston accumulator serves as a medium accumulator in the SMG-hydraulic system. In the pressure accumulator a piston separates the nitrogen filling from the hydraulic oil. The preload pressure of the filling is almost 39 bar in new condition. With increasing age, the preload loses its pressure. If it falls below 29 bar, the piston accumulator must be replaced.

Piston accumulator

Overview solenoid valves

Top view pump

Proportional pressure regulator (gear 1, 3, 5 (A); gear 2, 4, 6 (D))

The two proportional pressure control valves each supply hydraulic oil to one side of the switching path cylinder. For the forward and backward movement, one side of the piston is supplied with pressure by a solenoid valve and the other solenoid valve returns the displaced volume of the opposite side of the piston to the tank in the hydraulic unit.

Proportional directional control valve (coupling (B); angle of selection (C))

The two proportional directional control valves in the hydraulic unit supply hydraulic oil to the slave cylinder of the clutch and to the cylinder for the selector angle. There are three positions:

  1. Pressure reduction: There is clutch operation or gear change. Both cylinders are directly connected to the oil tank.
  2. Pressure build-up: If there is a clutch operation or a gear is to be shifted, hydraulic oil is fed from the piston accumulator into the cylinders. The solenoid valves require just under 1.1 to 2 amperes here.
  3. Hold pressure: When the clutch is disengaged or the selector shaft has reached its position, the oil pressure is maintained in both cylinders.
Solenoid valve
Pressure control valve
Solenoid valve
Directional control valve

 

Error code              Error description              possible reason Measures
16 (0x10) Control of solenoid valve Switching travel forward
  • Solenoid valve switching travel Before defective
  • Short circuit
  • open circuit
  • Solenoid valve Switching travel Before Replace
  • Check wiring harness and plug connections
17 (0x11) Control of solenoid valve Switching travel back
  • Solenoid valve switching travel back defective
  • Short circuit
  • open circuit
  • Replacesolenoid valve switching travel back
  • Check wiring harness and plug connections
18 (0x12) Solenoid valve control Selecting angle
  • Solenoid valve selection angle defective
  • Short circuit
  • open circuit
  • Replacesolenoid valve selection angle
  • Check wiring harness and plug connections
19 (0x13) Control Shift Lock
  • Shift-Lock magnet defective
  • Short circuit
  • open circuit
  • Replacing the Shift-Lock magnet
  • Check wiring harness and plug connections
20 (0x14) Starter release
  • Starter relay defective
  • Short circuit
  • open circuit
  • Replace starter relay
  • Check wiring harness and plug connections
21 (0x15) Relay hydraulic pump
  • Relay hydraulic unit is suspended
  • Short circuit
  • open circuit
  • Replacerelay hydraulic unit
  • Check wiring harness and plug connections
22 (0x16) Control of reversing light switch
  • Short circuit
  • open circuit
  • Check wiring harness and plug connections
23 (0x17) Solenoid valve control Clutch
  • Magnetic valve clutch defective
  • Short circuit
  • open circuit
  • Magnetic valve Replace clutch
  • Check wiring harness and plug connections
32 (0x20) Evaluation of gearbox input speed
  • Speed sensor defective
  • Short circuit
  • open circuit
  • Replace speed sensor
  • Check wiring harness and plug connections
33 (0x21) Evaluation of engine speed (Sensor)
  • Sensor defective
  • Short circuit
  • open circuit
  • Sensor swap
  • Check wiring harness and plug connections
34 (0x22) Gearbox temperature
  • Temperature sensor defective
  • Short circuit
  • open circuit
35 (0x23) Evaluation hydraulic pressure sensor
  • Pressure sensor defective
  • Short circuit
  • open circuit
36 (0x24) Evaluation of the position encoder angle of selection
  • Gang detection sensor defective
  • Short circuit
  • open circuit
37 (0x25) Evaluation of position encoder switching travel
  • Gang detection sensor defective
  • Short circuit
  • open circuit
38 (0x26) Evaluation of longitudinal acceleration
  • Longitudinal acceleration sensor defective
  • Short circuit
  • open circuit

 

  • Replace longitudinal acceleration sensor
  • Check wiring harness and plug connections
39 (0x27) Hydraulic temperature
  • Temperature sensor defective
  • Short circuit
  • open circuit
40 (0x28) Evaluation PLCD-Sensor for coupling position
  • PLCD-Sensor defective
  • Clutch defective
48 (0x30) gear not engageable
  • Gang detection sensor defective
  • Short circuit
  • open circuit
49 (0x31) Gear jumper
  • Gang detection sensor defective
  • Short circuit
  • open circuit
50 (0x32) Angle of selection not adjustable
  • Gang detection sensor defective
  • Solenoid valve selection angle defective
  • Short circuit
  • open circuit
  • Replace gait detection sensor
  • Replace solenoid valve selection angle
  • Check wiring harness and plug connections
51 (0x33) Evaluation of bonnet contact in driving mode
  • one of the two hood contacts defective
  • Replace defective hood contact
52 (0x34) Evaluation of bonnet contact while stationary
  • one of the two hood contacts defective
  • Replace defective hood contact
53 (0x35) Printing ribbon underrun HE
  • Relay hydraulic unit is suspended
  • worn electric motor
  • Pressure sensor defective
  • Leakage in the hydraulic system
  • Short circuit
  • open circuit
  • Replace relay hydraulic unit
  • Replace electric motor
  • Replace pressure sensor
  • Seal leakage
  • Check wiring harness and plug connections
54 (0x36) Printing ribbon overrun HE
  • Relay hydraulic unit is suspended
  • Pressure sensor defective
55 (0x37) Switch-on frequency of hydraulic unit
  • worn electric motor
  • Preload pressure of the piston accumulator no longer OK
  • SMG Relay hangs
  • Internal leakage at high temperatures
  • external leakage
  • Level of hydraulic oil too low
  • Air in the system
  • Temperature sensor defective
  • Short circuit
  • open circuit
56 (0x38) Duty cycle hydraulic unit
  • worn electric motor
  • Preload pressure of the piston accumulator no longer OK
  • SMG Relay hangs
  • Internal leakage at high temperatures
  • external leakage
  • Level of hydraulic oil too low
  • Air in the system
  • Temperature sensor defective
  • Short circuit
  • open circuit
57 (0x39) Misuse hydraulic unit
  • worn electric motor
  • Preload pressure of the piston accumulator no longer OK
  • SMG Relay hangs
  • Internal leakage at high temperatures
  • external leakage
  • Level of hydraulic oil too low
  • Air in the system
  • Temperature sensor defective
  • Short circuit
  • open circuit
58 (0x3A) gear not selectable
  • Air in the system
  • Venting and adapting
59 (0x3B) Clutch actuation
  • PLCD-Sensor defective
  • Clutch defective
  • Release bearing defective
80 (0x50) SMG Control unit internal error
  • SMG Control unit defective
  • Short circuit
  • open circuit
  • SMG Replace control unit
  • Check wiring harness and plug connections
81 (0x51) Evaluation ESTATE
83 (0x53) Gearbox adaption
  • Adaptation not successfully performed
  • Correct displayed error in case of adaptation abort
84 (0x54) General Adaptation
  • Adaptation not successfully performed
  • Correct displayed error in case of adaptation abort
85 (0x55) Adaptation of the clutch
  • Adaptation not successfully performed
  • Correct displayed error in case of adaptation abort
86 (0x56) bleeding
87 (0x57) Modes of action
88 (0x58) Adaptation values Gearbox
97 (0x61) Power supply
  • Short circuit
  • open circuit
  • Check wiring harness and plug connections
98 (0x62) Sensor power supply A
  • Vsensor < 4.5 V
  • Vsensor > 5.5 V
  • Influences longitudinal acceleration sensor, selection angle 1, switching travel 1
  • Check wiring harness and plug connections
99 (0x63) Sensor power supply B
  • Vsensor < 4.5 V
  • Vsensor > 5.5 V
  • Influences hydraulic pressure sensor, selection angle 2, switching travel 2
  • Check wiring harness and plug connections
100 (0x64) Power supply for solenoid valves Switching travel
  • Short circuit
  • open circuit
  • Check wiring harness and plug connections
101 (0x65) Power supply for solenoid valves Clutch and angle of rotation
  • Short circuit
  • open circuit
  • Check wiring harness and plug connections
114 (0x72) Evaluation selector lever
  • Selector lever defective
  • Replace selector lever
115 (0x73) Evaluation consumer switch-off VA
116 (0x74) Evaluation Program selector switch Plus
117 (0x75) Evaluation Program selector switch Minus
118 (0x76) Evaluation steering wheel switch +
119 (0x77) Evaluation of steering wheel switch -
120 (0x78) Evaluation ignition lock signal
128 (0x80) Faulty CANmessage / bus CAN error
  • Short circuit
  • open circuit
  • Check wiring harness and plug connections
129 (0x81) CAN-Error
  • Short circuit
  • open circuit
  • Check wiring harness and plug connections
144 (0x90) Evaluation door contact via CAN
  • Door contact sensor defective
  • Short circuit
  • open circuit
  • Replace door contact sensor
  • Check wiring harness and plug connections
145 (0x91) Evaluation speed rear left
  • Wheel speed sensor defective
  • Speed sensor (gear) defective
  • Short circuit
  • open circuit
  • Replace wheel speed sensor
  • Speed sensor (gearbox) defective
  • Check wiring harness and plug connections
146 (0x92) Evaluation speed rear right
  • Wheel speed sensor defective
  • Speed sensor (gear) defective
  • Short circuit
  • open circuit
  • Replace wheel speed sensor
  • Speed sensor (gearbox) defective
  • Check wiring harness and plug connections
147 (0x93) Evaluation speed front left
  • Wheel speed sensor defective
  • Speed sensor (gear) defective
  • Short circuit
  • open circuit
  • Replace wheel speed sensor
  • Speed sensor (gearbox) defective
  • Check wiring harness and plug connections
148 (0x94) Speed evaluation front right
  • Wheel speed sensor defective
  • Speed sensor (gear) defective
  • Short circuit
  • open circuit
  • Replace wheel speed sensor
  • Speed sensor (gearbox) defective
  • Check wiring harness and plug connections
149 (0x95) Speed evaluation (more than one signal)
  • Wheel speed sensor defective
  • Speed sensor (gear) defective
  • Short circuit
  • open circuit
  • Replace wheel speed sensor
  • Speed sensor (gearbox) defective
  • Check wiring harness and plug connections
150 (0x96) Evaluation of engine speed (CAN)
  • Sensor defective
  • Short circuit
  • open circuit
  • Sensor swap
  • Check wiring harness and plug connections
151 (0x97) Evaluation of service brake signals via CAN
  • Longitudinal acceleration sensor defective
  • Short circuit
  • open circuit
  • Replace longitudinal acceleration sensor
  • Check wiring harness and plug connections
152 (0x98) Steering angle evaluation via CAN
  • Defective steering angle sensor
  • Short circuit
  • open circuit
  • Replace steering angle sensor
  • Check wiring harness and plug connections
153 (0x99) Evaluation of lateral acceleration over CAN
  • Sensor defective
  • Short circuit
  • open circuit
  • Sensor swap
  • Check wiring harness and plug connections
154 (0x9A) Evaluation of longitudinal acceleration over CAN
  • Longitudinal acceleration sensor defective
  • Short circuit
  • open circuit
  • Replace longitudinal acceleration sensor
  • Check wiring harness and plug connections
155 (0x9B) Evaluation of accelerator pedal value via CAN
  • Short circuit
  • open circuit
  • Check wiring harness and plug connections
176 (0xB0) Safety concept Level 2 Gearbox
177 (0xB1) Safety concept level 2 Coupling
178 (0xB2) Safety concept level 3
179 (0xB3) Safety concept level 2 RAM
180 (0xB4) Safety concept level 2 INPUT
255 (0xFF) unknown fault location
Pin Connector Designation Cable color
1
2 Pressure sensor + green white
3 Temperature sensor - brown
4 Pressure sensor - brown
5 Temperature sensor + white
6 Pressure sensor Signal orange
7
8 Electric motor - brown
9 Valve Coupling (B) red and white
10 Valve Coupling (B) yellow
11 Electric motor + red yellow
12 Valve Selector angle (C) black yellow
13 Valve Selector angle (C) black red
14 Valve gear 2, 4, 6 (D) black and white
15 Valve gear 2, 4, 6 (D) black violet
16 Valve gear 1, 3, 5 (A) blue
17 Valve gear 1, 3, 5 (A) black blue
18