LI27 00-N-048696

Automatic transmission oil loss in area
of wiring harness and oil pan gasket
Topic number
LI27.00-N-048696
Version
3
Function group
27.00 General
Date
07-24-2017
Validity
Transmission 722.680/681/682/683/684/685 in model
639, 903, 904, 905, 906
Reason for change
Distribution revised
Reason for block
Complaint:
Automatic transmission oil loss in the area of the wiring harness and oil pan gasket and/or in the wiring harness. Different remedial action is necessary based on the type of complaint (a or b).
a) Transmission oil loss in area of pilot bushing, oil pan
b) There is transmission oil in the wiring harness.
Cause:
The following causes may apply and require different repair methods:
a) Due to insufficient sealing of the large O-ring of the pilot bushing outwards, transmission oil has distributed itself in
the area of the plug/oil pan gasket
b) Due to insufficient sealing of the small O-ring of the pilot bushing, there is transmission oil in the wiring harness.
Remedy:
Carry out remedies according to the complaint:
a) Clean the transmission in the affected area, spray with leak detector spray and perform road test. If no oil escape
can be detected after the road test or can only be detected in the area of the pilot bushing, only replace the pilot bushing. Use damage code 27270 04.
b) !!!!Procedure modified !!!!
Replace pilot bushing with seal rings.
The supporting body is not the cause of leakage complaints at the pilot bushing and must not be replaced on these
grounds.
Allow the wiring harness to drip and blow out the plugs at the transmission end and control unit end with compressed
air. In addition the control unit contacts must be blown dry.
The contacts can then be sprayed lightly with commercially available contact spray. Use damage code 27270 04.
Notes:
In the course of the production and inspection processes, the pilot bushing is coated with oil. Because of this, oil from
manufacture can therefore enter the pilot bushing and form a small puddle (see attachment). However, a larger quantity of oil should not flow out of the pilot bushing when the pilot bushing (at the wiring harness end) is pulled. If this is
the case, the pilot bushing must be replaced.
When connecting the wiring harness to the transmission, make sure that the wiring harness is routed free of tension.
No tensile forces may be transferred to the plug by the wiring harness. Increase outer cable length if necessary (no
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reason to replace a wiring harness). The pictures in the attachment show examples of bad (Figure 2) and good (Figure 1) routing.
The pilot bushing may only be disassembled/assembled at transmission oil temperatures below 50 °C in order to avoid damaging the electrical set/supporting member.
Attachments
File
Description
Fuhrungsbuchse_Olmenge ok.pdf
Pilot bushing is OK
1.jpg
Example of tension-free, good line routing
2.jpg
Example of poor line routing which leads to an effect of
forces on the plug
Symptoms
Power transmission / Automatic transmission / Function / General
Power transmission / Automatic transmission / Leakage / Leaks
Parts
Part number
ES1 ES2 Designation
Quantity Note
A 000 989 03 59
Leak detector spray
1
A 203 540 02 53
Pilot bushing
1
EPC
Only when required
X
X
Operation numbers/damage codes
Op. no.
Operation text
27-5001
27-4980
Time
Damage
code
Note
REMOVE/INSTALL/SEAL PILOT BUSHING ON ELECTROHYDRAULIC CONTROLLER UNIT; REPLACE IF NECESSARY
27270 04
Model 903-906 Pilot bushing - leaky
The listed damage code is not to
be considered as an acceptance of
costs. The general guidelines in the
Warranty Manual apply.
REMOVE/INSTALL/SEAL PILOT BUSHING ON ELECTROHYDRAULIC CONTROLLER UNIT; REPLACE IF NECESSARY
27270 04
Model 639 Pilot bushing - leaky
The listed damage code is not to
be considered as an acceptance of
costs. The general guidelines in the
Warranty Manual apply.
WIS-References
Document number
Title
Note
Allocation
AR27.00-S-0101S
Inspect ATF level in automatic transmission, add
ATF if necessary
Model 639
Remedy
AR27.00-S-0200-01S
Drain transmission oil from Model 639
torque converter and transmission
Remedy
AR27.10-S-0500-01SV
Disconnect/connect plug
Remedy
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© Copyright Daimler AG
Model 639
KATSELF
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AR27.19-D-4980A
Remove/install pilot bushing Model 901-905
of electrohydraulic controller
unit
Remedy
AR27.00-D-0101A
Inspect ATF level in automatic transmission, add
ATF if necessary
Remedy
AR27.19-D-4980B
Remove/install pilot bushing Model 906
of electrohydraulic controller
unit
Remedy
AR27.00-D-0100H
Inspect ATF level in automatic transmission, add
ATF if necessary
Remedy
Model 901-905
Model 906
Attachments
1.jpg:
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2.jpg:
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