AR46.20-P-0701AK Remove/install motor controller unit of electric power steering (ES) 10.11.

11
MODEL 169.0 /3 with ENGINE 266.920 /940 /960 /980, 640.940 /941 /942
MODEL 245.2 with ENGINE 266.920 /940 /960 /980, 640.940 /941

P46.20-2295-09

Shown on engine 266.920

1 Motor controller unit 6 Electrical connector N68 Electrical power steering (ES)
2 Bolts 7 Screw control unit
3 Shield 8 Steering coupling N68x1 Steering assist control unit (ES)
connector 1
N68x2 Steering assist control unit (ES)
connector 2

1 Motor controller unit

9 Screw
10 Rack-and-pinion steering
11 Wiring harness
12 Bracket
13 Sealing ring
14 Damper coupling

N68 Electrical power steering (ES)

control unit

P46.20-2245-05

Modification notes
16.6.05 Disconnect steering coupling modified Operation step 4, 21

Remove
When working on the rack-and-pinion steering
(10) great attention must be paid to
cleanliness as contamination in the interior
may result in irreparable damage to the rack-
and-pinion steering (10)
1.1 Remove air filter box Engine 266 AR09.10-P-1050AK
1.2 Remove air filter housing and intake air scoop Engine 640 AR09.10-P-1150AL
© Mercedes-Benz AG, 4/4/21, L/10/20, ar46.20-p-0701ak, Remove/install motor controller unit of electric power steering (ES) Page 1 of 3
MODEL 169.0 /3 with ENGINE 266.920 /940 /960 /980, 640.940 /941 /942 MODEL 245.2 with ENGINE 266.920 /940 /960 /980, 640.940 /941
2 Place rack-and-pinion steering (10) in center AR46.20-P-0500-01AK
position
3 Fix steering wheel in position using the On a disengaged steering coupling (8) the
retainer. steering wheel should not be turned because
the spiral contact coil will be destroyed.
*129589012100
4 Unscrew the bolt (7) from the steering Disconnect if steering coupling (8) is not AR46.10-P-8000-01AK
coupling (8) and separate steering coupling corroded.
(8)
Only disconnect a corroded steering coupling AR46.10-P-8000-01AL
(8) for left-hand drive vehicles up to chassis
end number 160000 (with model 169) or
chassis end number 008500 (with model
245).
*203589023300
Body jig saw
gotis://K_58.1_01.0
Wet/dry vacuum cleaner
gotis://P_00.12_06.0
5.1 Remove steering shaft Only if steering shaft has been cut open AR46.10-P-7300AK
because of a corroded steering coupling (8).
6 Undo screws (2) of shield (3) on electric The electric power steering (ES) control
power steering (ES) control unit (N68) unit (N68) is integrated into the engine
controller unit (1) and may not be separately
removed or replaced.
7.1 Remove shield (3). On model 169
7.2 Remove shield (3) and lay on front axle carrierOn model 245
The shield (3) can only be removed from
the engine compartment when the engine
controller unit (1) is removed
8 Unplug electrical connector (6), steering
assist control unit (ES) connector 1 (N68x1)
and steering assist control unit (ES) connector
2 (N68x2) at electric power steering (ES)
control unit (N68)
9 Unscrew screws (9) for engine controller unit Observe installation position of bracket
(1) (12) and electrical wiring harness (11).
10 Route engine controller unit (1) from the rack- Use a lint free rag to protect the rack-and-
and-pinion steering (10) and remove pinion steering (10) and motor controller unit
(1) against dirt, as contamination in the
interior may irreparably damage the rack-and-
pinion steering (10).
11.1 Remove shield (3) from engine compartment On model 245
12 Check sealing ring (13) and damper coupling Installation: Check correct seating of
(14), replace if necessary sealing ring (13) and damper coupling (14).
Install
13.1 Lay shield (3) in engine compartment on front On model 245
axle carrier
14 Insert engine controller unit (1) into the rack-
and-pinion steering (10)
15 Turn-in screw (9) of engine controller unit (1) Observe installation position of bracket
(12) and electrical wiring harness (11).
*BA46.20-P-1003-01I
16 Connect up electrical connector (6), steering
assist control unit (ES) connector 1 (N68x1)
and steering assist control unit (ES) connector
2 (N68x2) at electric power steering (ES)
control unit (N68)
17 Mount shield (3) and fasten with screws (2) to Installation: In order to achieve a proper *BA46.20-P-1005-01I
electric power steering (ES) control unit (N68) screwed connection when installing a new
engine controller unit (1), the torque, with
which the screws (2) are tightened should be
increased by 10 Nm.
The first time they are turned-in the screws (2)
will cut the required thread into the electric
power steering (ES) control unit (N68).
18 Place rack-and-pinion steering (10) in center AR46.20-P-0500-01AK
position
*203589043103
19.1 Calibrate the torque sensor of the motor Only when installing new motor controller unit
controller unit (1) using STAR DIAGNOSIS (1).
No work may be performed on the vehicle
during the comparison, as it may be
negatively influenced.

© Mercedes-Benz AG, 4/4/21, L/10/20, ar46.20-p-0701ak, Remove/install motor controller unit of electric power steering (ES) Page 2 of 3
MODEL 169.0 /3 with ENGINE 266.920 /940 /960 /980, 640.940 /941 /942 MODEL 245.2 with ENGINE 266.920 /940 /960 /980, 640.940 /941
 The steering coupling (8) must not yet be
connected to the rack-and-pinion steering
(10).
Connect STAR DIAGNOSIS and read out AD00.00-P-2000-04AK
fault memory
STAR DIAGNOSIS diagnosis system
20.1 Install steering shaft Only if steering shaft has been cut open AR46.10-P-7300AK
because of a corroded steering coupling (8).
21 Connect steering coupling (8) with the rack- When in the input condition the steering AR46.10-P-8000-01AK
and-pinion using nut (10) and bolt (7). coupling (8) is not corroded.
Grease *BR00.45-Z-1006-06A
*BA46.10-P-1001-01H
When in the input condition the steering AR46.10-P-8000-01AL
coupling (8) is not corroded only on left-hand
drive vehicles up to chassis end number
160000 (on model 169) or up to chassis end
number 008500 (on model 245).
Grease *BR00.45-Z-1006-06A
*BA46.10-P-1001-01H
22 Remove retainer from steering wheel *129589012100
23.1 Install air filter housing and intake air scoop Engine 640 AR09.10-P-1150AL
23.2 Install air filter box Engine 266 AR09.10-P-1050AK

Steering shaft

Number Designation Model Model

169 245

BA46.10-P-1001-01H Clamp screw, steering coupling to rack-and- Nm 20 20

pinion steering

Steering gear

Number Designation Model Model

169 245

BA46.20-P-1003-01I Bolt, motor controller unit (ES) to rack-and- Nm 23 23

pinion steering

BA46.20-P-1005-01I Bolt, heat shield to motor controller unit (ES) Test torque Nm 10 10

129 589 01 21 00 203 589 02 33 00 203 589 04 31 03

Holding device Puller Socket wrench

Repair materials
Number Designation Order number
BR00.45-Z-1006-06A Anticorrosion grease 40 g / DB supply specification 6834.00 A 001 989 37 51 10

© Mercedes-Benz AG, 4/4/21, L/10/20, ar46.20-p-0701ak, Remove/install motor controller unit of electric power steering (ES) Page 3 of 3
MODEL 169.0 /3 with ENGINE 266.920 /940 /960 /980, 640.940 /941 /942 MODEL 245.2 with ENGINE 266.920 /940 /960 /980, 640.940 /941