No. 173-21-1

Service
Technical Information
173/21 ENU
1950
1
Warning Message "Coolant Temperature Too High": Checking Coolant Pump and
Change-Over Valve (173/21)
Revision:
This bulletin replaces bulletin Group 1 173/21, dated December 23, 2021.
Model Year:
As of 2017
Model Line:
Panamera (971)
Concerns:
Change-over valve for coolant pump
Information:
The customer complains about a warning message 'Coolant temperature too high'. A faulty coolant
pump is detected as the cause. Internal tests have shown that in some cases, the cause of a faulty
coolant pump is due to a faulty change-over valve in the coolant pump.
Action required: If the coolant pump is faulty or leaking, also check the change-over valve for the coolant pump and
replace it if necessary.
Required tools, parts and materials
Tool:
•
•
•
9900 - PIWIS Tester 3
Hand vacuum pump, e.g. VAS 6213 - Hand vacuum pump
Battery charger with a current rating of at least 90 A and - if required - also with a current and
voltage controlled charge map for lithium starter batteries, e.g. VAS 5908 90A battery
charger
For further information about the battery chargers to be used, see the corresponding Workshop Manual.
 Workshop Manual '270689 Charging vehicle electrical system battery'
Parts Info:
Required parts:
Part No.
Designation
– Location
Number
PAB906283
 Change-over valve
– Coolant pump
1 pc(s)
and/or
9A712101304
 Coolant pump
1 pc(s)
Parts required for replacing the coolant pump:
9A712111903
 Seal
– Coolant pump
AfterSales
1 pc(s)
Dec 19, 2022
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Materials:
Technical Information
ENU 173/21
1950
9A712117100
 Sealing ring
– Coolant pipe above coolant pump
1 pc(s)
9A700565200
 O-ring (17 x 3)
– Coolant pipe above coolant pump
1 pc(s)
9A712143713
 Sealing ring (41.8 x 1.85)
Disconnect coolant pipe for coolant pump
1 pc(s)
9A700792000
 O-ring (31.34 x 3.53-N)
Disconnect coolant pipe for coolant pump
1 pc(s)
Required materials (usually already available at the Porsche dealer):
Part No.
00004330501
00004330516
Designation
– Location
 Lubricant
– O-rings
 Coolant additive
Quantity
5 grams/ 0.18 oz
0.5 liter/ 16.9 fl oz
Preparatory work
Work Procedure: 1
Remove air guide.  Workshop Manual '243619 Removing and installing air guide (V6 turbo)'
2
Remove belt pulley.  Workshop Manual '195319 Removing and installing pulley (V6 turbo)'
3
Connect a suitable battery charger with a current rating of at least 90 A, e.g. battery charger
90A, to the jump-start terminals in the luggage compartment and switch it on.  Workshop Manual
'270689 Charging vehicle electrical system battery'
4
Place driver’s key in emergency start tray.
5
9900 - Connect PIWIS Tester 3 to the vehicle
communication module (VCI) via the USB cable.
Then connect the communication module to the
vehicle and switch on the PIWIS Tester.
6
Switch on ignition.
7
On the PIWIS Tester start screen, call up the 'Diagnostics' application.
The vehicle type is then read out, the diagnostic application is started and the control unit selection screen
is populated.
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AfterSales
Emergency start tray
Service
Technical Information
173/21 ENU
1950
1
Checking change-over valve for coolant pump and replacing it if necessary
Work
Procedure:
Position of change-over valve and coolant pump
1
Pull vacuum hose  Position of change-over valve and coolant pump -1- off the coolant pump 
Position of change-over valve and coolant pump -2-.
2
Pull off vacuum hose  Position of change-over valve and coolant pump -4- from the control valve
 Position of change-over valve and coolant pump -3-.
3
VAS 6213 - Hand vacuum pump must be  Position of change-over valve and coolant pump -3connected to the change-over valve  Position of change-over valve and coolant pump -4- on the
vacuum hose connection. Then build up vacuum.
Information
Stop the test procedure if a vacuum cannot be built up. In this case, the change-over valve is faulty
and must be replaced. Continue with Step 5. If a vacuum can be built up, continue with Step 4.
4
Perform drive link test:
4.1
Select Engine electronics (DME) control unit.
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Service
Technical Information
ENU 173/21
1950
4.2
Select the Drive links/checks menu.
4.3
Select Drive links and press •F12“ Next to confirm.
4.4
Select 'Activation of vacuum switchover valve for main coolant pump' and press
•F8“ to start.
•
•
If the vacuum in the vacuum pump display changes, the change-over valve  Position
of change-over valve and coolant pump -3- is intact. Continue with Step 4. In this case,
only  Position of change-over valve and coolant pump -2- replace the coolant pump if
it is faulty.
If the vacuum in the vacuum pump display does not change, the change-over valve 
Position of change-over valve and coolant pump -3- and the coolant pump  Position of
change-over valve and coolant pump -2- must be replaced, if necessary, if the coolant
pump is  Position of change-over valve and coolant pump -2- also faulty.
 Workshop Manual '195019 Removing and installing coolant pump (V6 biturbo)'
5
VAS 6213 - Hand vacuum pump must now be disconnected from the vacuum hose  Position of
change-over valve and coolant pump -1-.
6
Install vacuum hose  Position of change-over valve and coolant pump -1- on coolant pump 
Position of change-over valve and coolant pump -2-.
Concluding work
Work Procedure: 1
Switch off ignition.
2
Disconnect 9900 - PIWIS Tester 3 from the vehicle.
3
Remove the driver's key from the emergency start tray.
4
Switch off and disconnect the battery charger.
5
Install belt pulley.  Workshop Manual '195319 Removing and installing pulley (V6 turbo)'
6
Install air guide.  Workshop Manual '243619 Removing and installing air guide (V6 turbo)'
Invoicing
Invoicing:
For documentation and invoicing in the event of a warranty, state the work items required depending on
the scope of work required and the specified PCSS encryption in the warranty claim:
APOS
Labor operation
19505520
Replace coolant pump
19505521
Replace coolant pump
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I No.
AfterSales
Service
Technical Information
173/21 ENU
1950
1
PCSS encryption:
Location (FES5)
19500
Coolant
Damage type (SA4)
5000
pump leakages
References:
 Workshop Manual '270689 Charging vehicle electrical system battery'
 Workshop Manual '243619 Removing and installing air guide (V6 turbo)'
 Workshop Manual '195319 Removing and installing pulley (V6 turbo)'
 Workshop Manual '195019 Removing and installing coolant pump (V6 biturbo)'
Important Notice: Technical Bulletins issued by Porsche Cars North America, Inc. are intended only for use by professional automotive technicians who have attended Porsche service training
courses. They are written to inform those technicians of conditions that may occur on some Porsche vehicles, or to provide information that could assist in the proper servicing of a vehicle. Porsche special
tools may be necessary in order to perform certain operations identified in these bulletins. Use of tools and procedures other than those Porsche recommends in these bulletins may be detrimental to the
safe operation of your vehicle, and may endanger the people working on it. Properly trained Porsche technicians have the equipment, tools, safety instructions, and know-how to do the job properly and
safely. Part numbers listed in these bulletins are for reference only. The work procedures updated electronically in the Porsche PIWIS diagnostic and testing device take precedence and, in the event of a
discrepancy, the work procedures in the PIWIS Tester are the ones that must be followed.
© 2022 Porsche Cars North America, Inc.
AfterSales
Dec 19, 2022
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