Engine Controls - ECM Update For A/C Efficiency
01 08 29Oct. 22, 2008
2018902
Vehicle Information
Condition
Update Programming ECM for AC Cooling Efficiency
NOTE:
The condition as described does not compromise operator visibility.
DO NOT diagnose or replace components due to A/C Performance BEFORE performing the update function as explained in this bulletin.
Technical Background
The A/C compressor will shut off too early under very light acceleration. This condition may lead to insufficient cooling efficiency in hot weather climates.
Production Solution
Software updated as of VIN: 1K_9M048612 for Jetta vehicles, Concern identified after end of production for Rabbit vehicles.
Affected ECM part numbers:
07K 906 055 M, N, P, Q
Service
PROCEDURE:
Engine Control Module Update - Programming (Flashing) using Software Version Management (SVM)
NOTE:
An Update Programming procedure (flash) may overwrite any "TUNED" ECM or TCM programming. A "TUNED" ECM or TCM is described as any ECM or TCM altered so as to perform outside the normal parameters and specifications approved by Volkswagen Group of America.
Current Tuned ECM or TCM requirements: If you encounter a vehicle with a "Tuned" ECM or TCM, your dealership must do the following before performing any procedure that updates ECM or TCM programming:
^ Notify the owner that their ECM or TCM was found to have been tuned
^ Notify the owner any damage caused by the tuning of the ECM or TCM (including any adverse emissions consequences) will not be covered by Volkswagen Group of America warranties.
^ Obtain the owner's written consent (see attached Control Module Tuning form) for any requested repair under warranty or outside warranty that requires flashing, which will automatically overwrite the "Tuned" program.
If the vehicle has a tuned ECM or TCM, ensure the Control Module Tuning Form has been filled out.
Vehicle requirements
Battery MUST have minimum no-load charge of 12.5 V (failure to maintain voltage during update process can lead to ECM failure) (use a Volkswagen approved Midtronics/InCharge 940 (INC-940) tester/charger to maintain battery voltage).
VAS 5051: connected to vehicle and to 110 V 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.
When performing the update programming procedure, ALL DTCs for all systems are erased.
DTCs linked to Guided Fault Finding function tests will be lost. Therefore, always address stored DTCs for Customer concerns unrelated to the update programming procedure first.
NOTE:
Non observance of the following points may lead to ECM failure. VAS 5051 or VAS 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 update programming procedure. Any appliances with high electromagnetic radiation (i.e. mobile phones) must be switched OFF.
Prior to launching VAS-PC application and starting control module update process, confirm tester screen saver and power settings in accordance with Special Tools and Equipment - Service Information Document # VSE-08- 18. Failure to do so may result in the tester entering power save mode during data transfer, and subsequent control module failure.
Tip:
To Update Programming using SVM, review and follow instructions in Technical Bulletin Instance 2014603 "Software Version Management".
The SVM Process must be completed in its entirety so the database receives the update confirmation response. A warranty claim may not be reimbursed if there is no confirmation response to support the claim.
WARNING:
Radiator Fan(s) may cycle ON high speed during the Update Process. There is a risk that personal injury may result if contact is made with spinning fan blades.
Keep hands and all objects away from Radiator Fan(s) during Update Process.
^ Update the Engine Control Module using the SVM Unit code as listed in the table.
Tip:
The procedure can be found in GFF under Functions/ Component Selection, Software Version Management, Adjust Software.
Warranty
Required Parts and Tools
No Special Parts required.
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.