Technical Service Bulletin
01-23-12 - Late Production - Update Programming DTC P2421 Engine-Motor Control Module -J623-

Transaction No.: 2072378/2

Condition
Applicable Vehicles
Model(s)

Year

Eng. Code

Jetta

2020 – 2021

1.4T
(DGXA, DJXA)

Trans. Code VIN Range From VIN Range To
All

All

All

Revision Table
Instance Number

Published Date

Version Number

Reason for Update

2072378/2

5/02/25

01-23-12

Included FTIV replacement
instructions.

2072378/1

12/11/23

01-23-12

Original publication.

CAUTION
If software updates or flash campaign/actions are performed on a vehicle, a charger with at least 70A charging current
MUST be used in order to avoid problems during software updates and flash campaign/actions.

Customer Complaint :
MIL-on with the following fault code stored in the Engine Control Module (ECM) Fault Memory:

DTC

Description

P242100 EVAP System Vent Valve Stuck Open

NOTICE
DO NOT diagnose or replace components due to the above fault before following the procedures outlined in this bulletin.

Technical Background
Monitoring strategy for FTIV diagnosis is too sensitive, causing erroneous DTCs.

Production Solution
Not applicable – vehicle is out of production.

Service
In addition to the software update detailed below, there is an improvement to the FTIV (fuel tank isolation valve / tank switch-off valve -N288- )
(Figure 1.), which is necessary in preventing erroneous occurrences of the P2421 fault code.
The FTIV / tank switch-off valve -N288- currently installed on the vehicle must be inspected, to verify whether an improved part has already
been installed. The FTIV / tank switch-off valve -N288- is mounted to the EVAP canister assembly, as shown below.

Figure 1.
Remove the EVAP canister assembly and inspect the face of the FTIV / tank switch-off valve -N288- . If the part is already updated, it will be part
number 5Q0.201.549.C. Alternatively, it may have a white paint marking or an 02S” printed after the part number, as shown in Figure 2.
•

If the part number is 5Q0.201.549.C, the FTIV / tank switch-off valve -N288- is already the updated component. In this case, DO NOT
replace it, and instead reinstall the EVAP canister assembly. Only the software update will be required.

•

If the part has a white paint mark or “02S”, the FTIV / tank switch-off valve -N288- is already the updated component. In this case, DO
NOT replace it, and instead reinstall the EVAP canister assembly. Only the software update will be required.

•

If the part number is not 5Q0.201.549.C, there is no white paint mark, and “02S” is not included on the FTIV / tank switch-off valve -N288- ,
the component must also be replaced in addition to the software update. Always refer to ETKA for the most up to date part number
information.

Figure 2.
Update-Programming Procedure:
CAUTION
The Midtronics battery charger must be connected to the vehicle battery for the duration of the programming, to ensure the
battery state of charge remains above 12.5 volts during the update process. If the battery drops below 12.5 volts, the
programming could fail which may result in damage to the control module. Control modules damaged by inadequate voltage
will not be covered under the warranty policy. The technician should verify the vehicle voltage prior to starting the update
process and should monitor the voltage for the duration of the update. The procedure may cancel itself if the hazard
warning lights are not switched ON. The hazard warning lights prevent the system from switching to bus sleep mode during
the update. ODIS-Service test should be updated to the latest GFF technical version 11.0.0 or higher and SW version
2.47.0 or higher.

DANGER
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!

CAUTION
Prior to launching the ODIS Service diagnostic applications and starting control module update process, confirm tester

screen saver and power settings in accordance with Diagnostic Hardware & Windows® - VHW-20-02 Change Power Options
After Windows®10 Upgrade. Failure to do so may result in the tester entering power save mode during data transfer, and
subsequent control module failure. When using a VAS 6150/X or 6160/X tester in conjunction with a VAS 6154 wireless
transmitter head for a flash procedure, connect a USB cable between the transmitter head and the tester. Failure to do so
may lead to errors during the flash procedure. VAS tools must only be used with their power adapters plugged in. Under no
circumstances should they be used on battery power alone during the programming procedure.

NOTICE
To Update-Programming using Software Version Management (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 or action is carried out that is not explicitly stated in the Technical Bulletin.

Update the Engine/Motor Control Module -J623- using the SVM Unit code as listed in the table below:

Model

Engine

Jetta

1.4T DGXA

Old Software Part
No.

Old Software
Version

New Software Part New Software Version (or
No.
higher)

SVM Unit
Code

04E 906 024 BB

7401
9945
9970
9971
9972
9973

04E 906 024 BB

9974

4D14

04E 906 024 BC

7400
9946
9970
9971
9972
9973

04E 906 024 BC

9974

4D14

04E 906 024 AB

Z842
6946
9944
9970
9971
9972
9973

04E 906 024 AB

9974

4D14

04E 906 024 BG

Z943
Z961
0905
1057
1520
2324

04E 906 024 BG

2889

4D14

04E 906 024 BH

Z943
Z961
0906
1056
2048
2325

04E 906 024 BH

2890

4D14

Z943
Z961
0907
1055
2049
2326

04E 906 024 BJ

04E 906 024 BJ

2891

4D14

The procedure can be found in GFF under Functions/ Component Selection, Software Version Management, Adapting Software.

NOTICE
Ensure ECM/TCM Tuning Form has been completed and signed by customer as required in SVM Technical Bulletin Instance
2014603.

Warranty
To determine if this procedure is covered under Warranty, always refer to the Warranty Policies and Procedures Manual
Model(s)

Year(s)

Eng. Code(s)

Trans. Code(s)

VIN Range From

VIN Range To

Jetta

2020 – 2021

1.4T DGXA

All

All

All

1)

SAGA Coding
Claim Type:

Use applicable Claim Type

1)

Service Number:

Damage
Code

HST

Damage Location (Depends
on Service No.)

2470

0039

--

-3ME 2)

Jetta

Parts Manufacturer
Labor Operation 3 ) : Charge Battery

27068950 = See Elsa for latest time units

Labor Operation 3 ) : Update Programming Engine/Motor Control
Module -J623-

24705599 = 50 TU max

Labor Operation 3 ) : Activated charcoal filter rem+reins

20251900 = See Elsa for latest time units

Labor Operation 3 ) : Replace FTIV / Tank switch-off valve -N288(ONLY if required per inspection)

20711958 = See Elsa for latest time units

Causal Part:

24705599
Diagnostic Time

4)

GFF Time expenditure

01500060 = Actual GFF print out

NO

Road Test

01210004 = 10 TU

YES

Technical Diagnosis

01320000 = 00 TU max.

NO

Claim Comment: Input “As per Technical Bulletin 2072378” in comment section of Warranty Claim.
1)

Vehicle may be outside any Warranty in which case this Technical Bulletin is informational only.

2)

Code per warranty vendor code policy.

3)

Labor Time Units (TUs) are subject to change with ELSA updates.

4)

Documentation required per Warranty Policies and Procedures Manual.

Required Parts and Tools

Part No:

Part Description

Quantity

5Q0201549C

Pressure Regulation Valve /
-N288-

1

Tool Description

Tool No:

VAS Diagnostic Tool

VAS 6150/X & VAS 6160/X and
ODIS Service with current online updates

VAS Battery Tester / Charger

VAS 5908

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.
© 2025 Volkswagen Group of America, Inc. All rights reserved. Information contained in this document is based on the latest information
available at the time of printing and is subject to the copyright and other intellectual property rights of Volkswagen Group of America, Inc., its
affiliated companies and its licensors. All rights are reserved to make changes at any time without notice. No part of this document may be
reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or
otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the publisher.

OWNER INFORMATION ABOUT CONTROL MODULE TUNING*
ACKNOWLEDGEMENT AND AUTHORIZATION FOR
REPROGRAMMING (REFLASHING) OF CONTROL MODULE(S)
*) “TUNING” is described as the addition of or modification of any component which causes a
Volkswagen vehicle to perform outside the normal parameters and specifications approved by
Volkswagen Group of America / Volkswagen Group Canada.

Date:
Dealer Number:
Vehicle Identification Number:
Repair Order Number:
Dealer stamp

I

, owner or driver of the above identified Volkswagen, confirm:

- “Tuning” as described above (especially power increasing modifications) has NOT been
performed on my vehicle.
- “Tuning” as described above has been performed on my vehicle and the following components
were modified or installed:

TUNING was performed by (Please provide Company name and telephone number, if you wish us
to contact them):

I understand that if my Control Module is determined to have been tuned, any damage caused by
the tuning of the Control Module (including adverse emissions consequences) will not be covered
by VWGoA / VGC warranties.
I am permitting an authorized Volkswagen Dealer to reflash (update) my Control Module, and by
doing so, I understand that this process will automatically overwrite (destroy) and permanently
delete any tuning program that was previously installed on the Control Module of my Volkswagen
vehicle.
By signing below, I fully acknowledge and understand that the tuning program will not be restored
and VWGoA / VGC, will not be liable in any way for the loss of tuning data.

Signature of Customer
E

2025 Volkswagen Group of America Inc.

All rights reserved. Information contained in this document is based on the latest information available at the time of printing and is subject to the copyright
intellectual property
rights of VGoA / VGCA Inc., its affiliated companies and its licensors. All rights are reserved to make changes at any time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or
other
and
by any means, .electronic, mechanical, photocopying, recording, or otherwise, nor may these materials be modified or reposted to other sites, without the prior expressed written permission of the publisher.