3

Service

Technical Information

84/17

3995
Noise Symptom/Jerking - Clicking Noise/Rough-Running Engine/Jerking Under Load With
Respect to Transfer Case: Programming all-wheel drive control unit/checking transfer
case (SY 84/17)
ENU

Information
Currently, a high percentage of warranty returned transfer cases are evaluated as "OK" during
testing by the supplier.
For this reason, the two previous symptom-based repair instructions are being replaced by these
symptom-based repair instructions:
1.  "Eliminating noise symptoms - Re-programming control unit for all-wheel drive (Creaking noise from
around the transfer case/SY0416) –  only relevant for vehicles from model year 2015 to 2016
and
2.  "Eliminating symptoms - Engine: Replacing transfer case (Rough-running engine, vehicle jerks
under load/SY2516)
in Repair Group 39 - Final drive.

Information
The "transfer case" is designed as an active all-wheel drive system that is dynamically adapted to the
respective driving state.
Power transmission between the front and rear axle is controlled electronically via the "all-wheel
drive servo motor (transfer case)" and the multi-plate clutches integrated in the transfer case.
 On all-wheel drive vehicles, the drive train can become strained at low speeds and when the
steering is turned sharply when "Off-road mode" is activated, depending on design.

Revision:

•

Under extreme conditions, the drive train can also become strained when "Off-road mode" is
deactivated.

•

Customers with little experience with all-wheel drive vehicles can interpret this behavior as a
fault, which in turn can result in incorrect diagnoses in the workshop.

This bulletin replaces bulletin dated September 22, 2017.
The Information note under “Symptom 1”, the first bullet point was amended to read:
“that were produced from model year 2015 to model year 2016 and”

Model Year:

As of 2011 up to 2017

Vehicle Type:

Cayenne (VR6 - 92A)/Cayenne S (92A)/Cayenne GTS (92A)/Cayenne Turbo (92A)/Cayenne
Turbo S (92A)/Cayenne S Diesel (V8 - 92A)

Equipment:

With transfer case

© 2017 Porsche Cars North America, Inc.

AfterSales

Nov 2, 2017
Page 1 of 8

3

Service
3995

With regard to
1:

ENU

Technical Information

84/17

1.  All-wheel drive servo motor (transfer case)  see "Symptom 1" below
Information
"Symptom 1" described below and the corresponding test procedure is relevant only for vehicles
 from model year 2015 to model year 2016.
 This procedure and remedial action must not be used for vehicles from model years 2011 to
2014.

Symptom 1:

Clicking noises can come from around the transfer case when driving slowly or when
manoevring in a parking garage.
Information
The customer complaint about a clicking noise (from the servo motor) can only occur on
vehicles:
•

that were produced from model year 2015 to model year 2016 and

•

with a software version lower than version 1010 in the all-wheel drive control unit.

Cause:

Clicking noises can come from around the transfer case when manoeuvring the vehicle (or driving slowly)
due to activation of the transfer case servo motor.

Remedial
Action:

Before doing any other work, the symptom must be simulated using a test procedure.
(Opening the door windows can be helpful when evaluating noises).
1

Conditions for the first test procedure:
•
•
•

Activate the Start/Stop function and
deactivate all sources of noise in the vehicle (Entertainment, ventilation, etc.).
A multi-story parking garage can be useful for acoustic reverberation.

•
•
•
•

On a straight stretch
from speeds less than 10 mph (20 km/h)
brake the vehicle to a standstill.
The best way of finding the clicking noise is by driving slowly and then stopping the vehicle.

 In the event of a distinct customer complaint, the clicking noise can already be heard on a straight
stretch with partial load accelerations.
 To correct the problem, re-program the all-wheel drive control unit. See "Procedure"
section below.
The measure is complete after programming the all-wheel drive control unit.

Nov 2, 2017
Page 2 of 8

AfterSales

© 2017 Porsche Cars North America, Inc.

Service

Technical Information
With regard to
2:

84/17

ENU

3995

3

Transfer case  see "Symptom 2" below
Information
"Symptom 2" described below and the corresponding test procedure is relevant for vehicles
 from model year 2011 to model year 2017.
 For vehicles from model year 2015, the test procedure described under "Symptom 1" must
be completed before doing any other work.

Symptom 2:

Symptoms to be checked:
•
•
•

Rough-running engine or
the vehicle vibrates or
the engine jerks under load.

Information
Generally, the vehicle can start jerking when driving in tight corners with a small radius and when Off-road
mode is activated.
This behavior is perfectly normal for all-wheel drive vehicles and is not a defect on the vehicle.
NOTICE
Driving with connectors on chassis components or control units disconnected.
•

Bearings in transfer case can be damaged.



Drive vehicle only at a maximum speed of 30 mph (50 km/h).



Do not drive vehicle in the upper load range or at full throttle.
1

Carry out the test procedure under the following conditions:
•
•
•

On a straight stretch
from speeds less than 10 mph (20 km/h)
accelerate the vehicle in the partial load range.

During this test procedure, if:
•
•

jerking can be felt, the test procedure under  (below) must also be carried out in order to
determine the exact cause.
no jerking is felt, see the information below about normal vehicle behavior:

© 2017 Porsche Cars North America, Inc.

AfterSales

Nov 2, 2017
Page 3 of 8

3

Service
3995

ENU

Technical Information

84/17

Information
Generally, the vehicle can start jerking when driving in tight corners with a small radius and when Off-road
mode is activated.
This behavior is perfectly normal for all-wheel drive vehicles and is not a defect on the vehicle.
2

Conditions for the test procedure:
•
•
•

Activate Off-road mode in the vehicle and
drive at low speed
into a tight bend with a small radius (high steering angle).

If jerking can be felt during this test procedure,  work through the following steps, depending
on which equipment is installed:
•
•

with PTV PLUS (controlled rear-differential lock) – I-no. 1Y1 continue with  2.1
without front/rear differential lock – I-no. 1Y0 continue with 

Information
Generally, the vehicle can start jerking when driving in tight corners with a small radius and when
Off-road mode is activated.
This behavior is perfectly normal for all-wheel drive vehicles and is not a defect on the vehicle.
2.1

Disconnect connector on the rear-differential lock control unit, see  Workshop Manual
'397519 Removing and installing control unit for rear-differential lock'.

2.2

Carry out the test procedure under the following conditions:
 Disconnecting the connector should prevent the vehicle from jerking due to a higher
rear-differential lock locking value.

3

2.3

Re-connect connector on the rear-differential lock control unit, see  Workshop Manual
'397519 Removing and installing control unit for rear-differential lock'.

2.4

If jerking still occurs even with the connector disconnected, continue with step  .

During the test procedure under step  , if jerking can be felt, the following test procedure
must still be carried out:
3.1

Disconnect connector on centre differential lock (plug connection on transfer gear
servo motor).

3.2

Carry out the test procedure under the following conditions:
•
•
•

Nov 2, 2017
Page 4 of 8

Activate Off-road mode in the vehicle and
drive at low speed
into a tight bend with a small radius (high steering angle).