5A43 - P178D (EGS)

5A43 - P178D

Information saved in
GS

Fault code
5A43 - P178D

Fault text
DKG: Pressure sensor, clutch 2: total failure

Fault description
Clutch 2 Pressure Sensor Circuit Range/Performance

Condition for fault identification
Test condition:
320 ms have elapsed since system start
Terminal 15 is active
Terminal 50 is not active
System is not in shutdown phase
The battery voltage is greater than 10V
Diagnosis of the sensor's power-supply voltage had not
detected any faults
Supplementary for offset diagnosis
Clutch has been drained
Terminal condition: Terminal 15 ON
Voltage condition:
UBat > 10V

Condition for fault memory entry
none

Action in service
Precondition: Engine off
1st step: Read out raw data [clutch 1 pressure sensor,
clutch 2 pressure sensor]
Tolerance range:
0.2 bar < pressure < 1.8 bar
1st step: Case 1: Pressure in one of the / both clutches
outside tolerance range 2nd step: Defective pressure
sensor(s)
Replace E-module
1st step: Case 2: Pressure in both clutches within tolerance
range 2nd step: Continue with fault analysis
2nd step: Read out fault category
Precondition: Both transmission units in neutral, engine
running
2nd step: Fault category 0, 2 (undefined, offset error):
Apply pressure to both clutches
Test routine 'Test_Offset_K1-2_02 '
2nd step: Case 1: Pressure difference Delete diagnostic fault code
2nd step: Case 2: Pressure difference > 0.5 bar 3rd step:
Pressure sensor offset too high
Replace E-module
2nd step: Fault category 4, 8 (short circuit or open wire):
Fault status
2nd step: Case 1: Persistent error 3rd step: Defective
pressure sensor(s)
Replace E-module
2nd step: Case 2: Sporadic error 3rd step: Delete
diagnostic fault code

Fault effect and breakdown warning
none

Driver information
Warning light:
ID 365/ 'Transmission malfunction! Drive gently'
Limp-home mode:
Gears 2, 4 and 6 not available (clutch circuit 2 locked out)

Service instruction
none