Diagnosis - Troubleshooting chart

1

Complaint

Possible cause

)

Remedy/Test step

Read out fault memory

ASD/4MATIC function indicator lamp (A1e25) comes on

Steering angle sensor (N49): Cable transposed; plug

12

sometimes when driving without skid

connection makes poor contact

23

10.0, 11.0, 12.0

Read out fault memory

ASD/4MATIC function indicator lamp (A1e25) comes on

Speed sensors (L6, L6/1, L6/2)

12

when driving round a tight bend without skid

23

13.0, 14.0, 15.0

ASD/4MATIC warning lamp (A1e24) comes on or flashes

Service valve (up to 05/91)

23

2

after starting engine, fault memory cannot be read out

)

4-MATIC valve control unit (A7/2)

33,

34

Oil pressure switch (A7/2s1)
Pressure oil pump

ABS warning lamp (A1e17) comes on approx. 20 s after

4MATIC - ABS signal cable open-circuit

23

7.0

starting engine (fault memory cannot be read out)

Severe roughness when driving round a tight bend (4MATIC

Service valve (up to 05/91)

33,

34

shift stage 1)

4MATIC valve control unit (A7/2)

43

Solenoid valves

Severe roughness when driving round a tight bend (4MATIC

Service valve (up to 05/91)

33,

34

shift stage 0)

4MATIC valve control unit (A7/2)

43

Solenoid valves

Constant higher oil consumption without external leaks

Seals on pistons of multiple-disc clutches defective

32

Booming, droning, vibrating when cornering (Service valve in

Rear engine mount has settled

Adjust or replace rear engine mount

test position)

1)

Note conditions for test

2)

To diagnose a potential hydraulic fault more rapidly, the plug connection (x1) at the valve control unit (A7/2, location under right rear seat bench) must be disconnected.
Remove pin 7 or 8 and connect plug coupling. If the fault memory can now be read out, there is a hydraulic fault.

Strona 1/1

© Daimler AG, 14.07.12, G/03/09 / dh0801pf20013x / 8.1 - 4MATIC 13 - Diagnosis - Troubleshooting chart Model 124.2/3