IMPORTANT SERVICE
INFORMATION FOR:
✓ SERVICE MANAGER
✓ SERVICE ADVISOR
✓ TECHNICIAN
✓ PARTS DEPARTMENT
✓ WARRANTY PERSONNEL

BULLETIN NUMBER:
CB25-L-001
ISSUE DATE:
NOVEMBER 2025
GROUP:
FUEL & EXHAUST

CUSTOMER SATISFACTION CAMPAIGN
P2201 CALIBRATION ERROR –
REPROGRAM ECM AND DCU (V2507)
AFFECTED VEHICLES
•

2025MY N-Series Vehicles Equipped with 5.2L (4HK1) Diesel
Engines

This Customer Satisfaction campaign bulletin supersedes Technical Service
bulletin SB25-L-001A. Please discard previous Technical Service bulletin SB25-L001A.
INFORMATION
CONDITION
In some 2025MY Isuzu N-Series vehicles equipped with 5.2L (4HK1) diesel engines,
operators may experience an illuminated Check Engine Malfunction Indicator Lamp (MIL)
with Diagnostic Trouble Code (DTC) P2201 NOx Sensor Circuit Performance Sensor 1.
We have determined a calibration error is causing this DTC to set. This DTC may be
resolved by reprogramming the Engine Control Module (ECM) and DEF Control Unit
(DCU) with revised calibrations.
CORRECTION
Isuzu dealers will reprogram the ECM and the DCU with the latest service calibrations.
This service will be performed free of charge until December 13, 2029 or until the
expiration of the New Truck Emission warranty coverage, whichever is longer.
VEHICLES INVOLVED
Involved are certain 2025MY Isuzu N-Series vehicles equipped with 5.2L (4HK1) diesel
engines.
NOTE: Dealers are to confirm vehicle eligibility prior to beginning repairs by using the
Isuzu Vehicle Information System (IVIS).
For dealers with involved vehicles, a report of involved vehicles containing the complete
vehicle identification number has been or will be provided. Dealers will not have a report
available if they have no involved vehicles currently assigned.

SERVICE PROCEDURE
1. Using the Isuzu Diagnostic Service System (IDSS), software version 16.4.4 or
later, reprogram the ECM and DCU to the latest service calibration numbers.
IMPORTANT: IDSS releases prior to 16.4.4 will not correct this condition. Be sure
IDSS is updated to or beyond version 16.4.4 before reprogramming.
NOTE: If only one control module has a newer calibration part number available,
it is only necessary to program that particular module.
2. Proceed to Applying the Campaign Label.
APPLYING THE CAMPAIGN LABEL
3. Using a ball-point pen, fill in a campaign label (Part No. 2-90028-700-0) with
Campaign Number V2507, Isuzu dealer code, and repair date.
4. Affix the campaign label onto the driver's side B-pillar.

CAMPAIGN CLAIM INFORMATION
Refer to the Isuzu ICS Claims Processing Manual for details on Campaign Claim
Submission. Submit only one claim as indicated below.
NOTE: Failure to submit campaign claims in a timely manner may result in delayed
payment. Accepted/Paid claims will change campaign status to “Closed” in IVIS.
Submit claims as quickly as possible in order to close the campaign and ensure
payment.
Labor Operation
Code

Description

Labor Time

V2507

DTC P2201 ECM & DCU Calibration Reprogram

0.6

*Includes 0.1 hours for administrative allowance.

2

DEALER RESPONSIBILITY
All vehicles in dealers' possession and subject to this customer satisfaction campaign
must be held and repaired per the service procedure of this campaign bulletin before
customers take possession of these vehicles.
Customers who have recently purchased vehicles sold from your vehicle inventory, and
for which there is no customer information indicated on the dealer listing, are to be
contacted by the dealer. Arrangements are to be made to make the required correction
according to the instructions contained in this bulletin. A copy of the customer letter is
provided in this bulletin for your use in contacting customers. Program follow-up cards
should not be used for this purpose, since the customer may not as yet have received the
notification letter.
In summary, whenever a vehicle subject to this customer satisfaction campaign enters
your vehicle inventory, or is in your dealership, you must take the steps necessary to be
sure the campaign correction has been made before selling or releasing the vehicle.
OWNER NOTIFICATION
Samples of the customer satisfaction campaign letters that are being sent to owners of
affected vehicles already retailed in the United States and Canada are attached below.

3

[SAMPLE OWNER LETTER – US]

CUSTOMER SATISFACTION CAMPAIGN
Campaign V2507
This notice applies to your vehicle,

DECEMBER 2025
Dear Customer,
The purpose of this notice is to inform you that Isuzu Commercial Truck of America, Inc. is
conducting a customer satisfaction campaign that affects 2025 model year Isuzu N-Series trucks
equipped with 5.2L (4HK1) diesel engines.
WHAT IS THE CONDITION?
In some 2025MY Isuzu N-Series vehicles equipped with 5.2L (4HK1) diesel engines, operators
may experience an illuminated Check Engine Malfunction Indicator Lamp (MIL) with Diagnostic
Trouble Code (DTC) P2201 NOx Sensor Circuit Performance Sensor 1. We have determined a
calibration error is causing this DTC to set. This DTC may be resolved by reprogramming the
Engine Control Module (ECM) and DEF Control Unit (DCU) with revised calibrations.
WHAT WE WILL DO
Isuzu dealers will reprogram the ECM and the DCU with the latest service calibrations. This
service will be performed free of charge until December 13, 2029 or until the expiration of the
New Truck Emission warranty coverage, whichever is longer.
WHAT YOU SHOULD DO
We recommend you contact your Isuzu dealer to schedule an appointment to bring your vehicle in
to have this service performed. Present this Owner Notification Letter at the time of your
appointment or refer to Customer Satisfaction Campaign Bulletin CB25-L-001. We estimate this
service may take approximately 36 minutes to perform. Additional time may be necessary
depending on how appointments are scheduled and processed at your dealership. To locate your
nearest dealer please use the dealer locator on our website at www.isuzucv.com.
If you have questions or concerns, please contact our Customer Relations Department at 1-866441-9638.
We regret any inconvenience this action may cause you.
Sincerely,
Isuzu Commercial Truck of America, Inc.
Important: If you have sold or traded your Isuzu vehicle, please enter the owner's name and address, if known, on the attached "Change of
Information" postcard, tear off at both perforations, and drop it in the mail. Postage has already been paid. We will contact the new owner.

4

[SAMPLE OWNER LETTER – CANADA]

CUSTOMER SATISFACTION CAMPAIGN
Campaign V2507
This notice applies to your vehicle
2025 model year ISUZU N-SERIES

DECEMBER 2025
Dear Customer,
The purpose of this notice is to inform you that Isuzu Commercial Truck of Canada, Inc. is
conducting a customer satisfaction campaign that affects 2025 model year Isuzu N-Series trucks
equipped with 5.2L (4HK1) diesel engines.
WHAT IS THE CONDITION?
In some 2025MY Isuzu N-Series vehicles equipped with 5.2L (4HK1) diesel engines, operators
may experience an illuminated Check Engine Malfunction Indicator Lamp (MIL) with Diagnostic
Trouble Code (DTC) P2201 NOx Sensor Circuit Performance Sensor 1. We have determined a
calibration error is causing this DTC to set. This DTC may be resolved by reprogramming the
Engine Control Module (ECM) and DEF Control Unit (DCU) with revised calibrations.
WHAT WE WILL DO
Isuzu dealers will reprogram the ECM and the DCU with the latest service calibrations. This
service will be performed free of charge until December 13, 2029 or until the expiration of the
New Truck Emission warranty coverage, whichever is longer.
WHAT YOU SHOULD DO
We recommend you contact your Isuzu dealer to schedule an appointment to bring your vehicle in
to have this service performed. Present this Owner Notification Letter at the time of your
appointment or refer to Customer Satisfaction Campaign Bulletin CB25-L-001. We estimate this
service may take approximately 36 minutes to perform. Additional time may be necessary
depending on how appointments are scheduled and processed at your dealership. To locate the
nearest Isuzu dealer you can visit our website at www.isuzutruck.ca or contact our Customer
Relations Department at the number listed below.
Isuzu Commercial Truck of Canada
Customer Relations
1-866-441-9638
If you have questions or concerns that your Isuzu dealer is unable to answer, please contact our
Customer Relations Department at 1-866-441-9638.
We regret any inconvenience this action may cause you.
Sincerely,
Isuzu Commercial Truck of Canada, Inc.
Important: If you have sold or traded your Isuzu vehicle, please enter the owner's name and address, if known, on the attached "Change
of Information" postcard, tear off at both perforations, and drop it in the mail. Postage has already been paid. We will contact the new
owner.

5