A/C - Low Heater Output in Cold Temperatures
19 07 03Nov. 6, 2007
2011082 Supersedes T.B. Group 19 number 05-02 dated December 19, 2005, due to incorrect Bosch ECM Part No. after update programming is complete.
Vehicle Information
Condition
Heater, Customer States Output Seems Insufficient
Customer states insufficient heater temperature output when driving in cold climate.
Technical Background
N/A
Production Solution
N/A
Service
Some vehicles may exhibit what seems to be lower heater output temperatures. This may be more noticeable in colder climates.
Automatic Transmission
For vehicles with an automatic transmission, install a new coolant
outlet hose, Part No. 1J0 122 058 K between the transmission cooler
and coolant pipe.
This new coolant outlet hose is equipped with a thermostat that will
inhibit coolant flow through the transmission cooler until the engine
reaches normal operating temperature.
The hose is directional (white arrow in illustration 19-A131) and should
be installed with the arrow on the thermostat pointing away from the
transmission cooler.
Manual Transmission
For vehicles equipped with manual transmission, the ECM will be re-programmed via a flash CD.
Procedure-Automatic Transmission
Note:
See Repair Manual group 19 and review all Cooling System Warnings and Notes.
^ Remove engine cover, see Repair Manual.
^ Remove air cleaner housing along with the mass air flow (MAF)
sensor.
^ Clamp off transmission cooler coolant outlet hose (black arrow), using Special Tool No. 3093, 3094 or equivalent.
^ Remove spring clip retaining coolant hose to transmission cooler using VAS 5024 spring clip pliers, and separate hose from cooler.
Tip:
Capture any fluid spillage using VAG 1306. Store / Dispose of, fluids in
correct and appropriately marked containers.
^ Raise and support vehicle, see Repair Manual group 00.
^ Remove spring clip retaining coolant hose to coolant pipe and separate hose from pipe.
^ Lower vehicle and remove cooler hose.
Installation
^ Observe directional arrow located on thermostat of Part No. 1J0
122 058 K. The arrow must point away from transmission cooler
^ Install hose clamps to new coolant hose.
^ Install hose onto transmission cooler and coolant pipe.
^ Install coolant hose clamp at transmission cooler using VAS 5024 spring clip pliers.
^ Raise and support the vehicle, see Repair Manual Group 00.
^ Install coolant hose clamp at coolant pipe using VAS 5024 spring clip pliers.
Tip:
When installing coolant hoses, route hoses stress-free so that they do not come into contact with other components (observe markings on coolant connection and hose).
^ Lower vehicle.
^ Remove coolant hose pinch off clamps.
^ Top up cooling system using appropriate coolant mixture, see Repair Manual group 19, Cooling System, Filling.
^ Start vehicle, allow to warm, turn engine off.
^ Top up cooling system using appropriate coolant mixture, see Repair Manual group 19, Cooling System, Filling.
Procedure-Manual Transmission
Tip:
The following "Update - Programming" (flashing) process may overwrite any "TUNED" ECM programming. A "TUNED" ECM is described as any ECM altered so as to perform outside the normal parameters and specifications approved by Volkswagen of America, Inc.
If you encounter a vehicle with a "Tuned" ECM, prior to performing the "Update - Programming" (flashing) procedure:
^ Your Dealership should place vehicle owner on notice in writing, that their ECM was found to have been tuned, and that any damage caused by the tuning of the ECM (including any adverse emissions consequences) will not be covered by Volkswagen of America, Inc. warranties.
^ For any repair requested by owner under warranty or outside warranty that requires flashing, which will automatically wipe out the "Tuning" program, your Dealership should advise the owner of the above and get
his written consent (see Control Module Tuning form) to the flashing procedure.
Tool requirements:
VAS 5051 or 5052 (with Base CD V.11.0 and the Brand CD V.11.79.01 or higher) with old diagnosis logs erased prior to start.
"Update - Programming" (flashing) CD, Part No: W42TDIPDHEATCD
Tip:
Additional copies of the "Update - Programming" CD (Literature Number W42TDIPDHEATCD) may be ordered from the Volkswagen Technical Literature Ordering Center or by calling from 8:00 a.m. to 8:00 p.m. EST Monday through Friday. This number can be dialed in both the United States and Canada.
Vehicle requirements:
^ Battery MUST have minimum no-load charge of 12.5V (failure to maintain voltage during update process can lead to ECM failure) (it is advised to use an approved battery charger to maintain battery voltage).
^ VAS 5051: connected to vehicle and to 110V AC Power supply at all times during procedure.
^ VAS 5052: connected to vehicle with battery voltage requirements met.
^ Any appliances with high electromagnetic radiation (i.e. mobile phones) switched OFF.
^ No Stored DTC's, erase any stored DTCs.
Tip:
Nonobservance of the following points may lead to ECM failure! VAS 5051 or 5052 must always be connected to the approved power supply at the approved voltages. Under no circumstances should the power supply be interrupted or the diagnostic connector unplugged during the flash procedure. Any appliances with high electromagnetic radiation (i.e. mobile phones) must be switched OFF.
"Update - Programming" (flashing) procedure, checking for update match Switch ignition ON.
^ Switch VAS 5051/5052 ON and insert flash CD into CD drive as soon as start screen appears.
Tip:
You must return to the start screen before starting a new (flashing)
session, otherwise the flashing CD will not be recognized by the tester.
^ Select "Vehicle Self Diagnosis" mode.
^ Select vehicle system "01-Engine electronics".
Program checks software level.
If software level of ECM MATCHES level indicated by Flashing CD:
"Update - Programming" (arrow) will not appear.
Tip:
The "Update - Programming" function is only available when the inserted flashing CD level and current vehicle ECM level are different.
If "Update - Programming" does not appear:
^ Programming (flashing ECM cannot be performed, continue to diagnose condition.
If software level DOES NOT match the level indicated on Flashing CD: "Update - Programming" (arrow) appears.
PRIOR to performing procedure to "Update - Programming" (flash) the ECM:
ALL fault memories must be interrogated and erased.
Tip:
Failure to erase ALL fault memories may cause "Update - Programming" (flashing) procedure to fail!re to fail!
^ Select Diagnosis function 06 "End output".
^ Select Diagnosis function 00 "Collection services".
^ Select "Check DTC memory - complete system" which will interrogate all fault memories.
Erase ALL fault memories.
^ Once ALL fault memories have been erased:
^ Select vehicle system "01-Engine electronics".
^ Select "Update - Programming" option at bottom of screen
(arrow).
"Update - Programming" (flashing), performing
After selecting "Update - Programming" function:
New program version 038997016H software level 8008 (Bosch) or
038997016J software level 8009 (NGK) and approximate timing for
update is shown on the VAS 5051/5052 screen.
^ By selecting the --> button, the programming procedure begins.
Similar screen appears:
The previous data in the ECM is erased and the new data is being transferred to the module from the flash CD.
Tip:
Approximate flashing time is 30 minutes.
Tip:
If, during the "Update - Programming", a fault message is displayed:
^ Confirm that VAS 5051 or VAS 5052 diagnostic tool power supply is adequate and that ALL appliances with high electromagnetic radiation (i.e. mobile phones) are switched OFF.
^ The "Update - Programming" (flashing) process must then be
started from the beginning using the "Repeat" button (arrow). DO
NOT use the "Cancel" button.
DO NOT select "Cancel" button.
Once "Update - Programming" (flashing) is complete:
Similar screen appears.
Old software level is still displayed at (arrows).
Tip:
New software level is not displayed until process is complete and fault
memories have been erased.
^ Select the "Print", then "Screen" button.
^ Attach print to vehicle Repair Order.
Once "Update - Programming" (flashing) is complete, the control module must be re-initialized.
^ Select the --> button.
The tester requests you to switch the ignition OFF.
^ Switch ignition OFF.
Wait at least 20 seconds before switching the ignition back ON (failure to wait at least 20 seconds may damage the ECM).
After waiting 20 seconds:
^ Switch ignition ON.
After switching ignition ON, the ECM has been re-initialized, however, fault memories must now be erased.
^ Select the "Continue button".
Fault memories, erasing after "Update - Programming" (flashing)
Due to the CAN bus system, fault messages will be stored in various Control Modules during programming.
To erase ALL fault memories:
^ Confirm by selecting the --> button.
Tip:
Erase fault memories takes approx. 15 minutes.
Similar screen appears.
Old ECM Part No. and software level still appear at (arrow)
Function ended appears at bottom of screen.
^ Finish update of the ECM by selecting the button.
Similar screen appears.
Updated software level 038997016 H software level 8008 (Bosch) or
03899-016 J software level 8009 (NGK) will appear at (arrow).
Flash CD can now be removed from VAS 5051 or VAS 5052 Diagnostic tool.
^ Print the ECM screen to verify ECM update software level.
^ Attach print to vehicle Repair Order.
Select "Go to" then select "Exit".
Tip:
It is not generally necessary to encode the ECM following the "update - Programming" (flashing procedure.
However, you must set the readiness code.
^ Set readiness code.
Use VAS 5051 or VAS 5052 to set readiness code.
Warranty
Required Parts and Tools
Additional Information
All part and service references provided in this Technical Bulletin are subject to change and/or removal. Always check with your Parts Dept. and Repair Manuals for the latest information.