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SUBJECT:

Calibration Support for Vehicles with Missing or Incorrect Electronic Control Module (ECU) or
Transmission Control Module (TCM) Calibrations

MODELS AFFECTED:

1000/2000/3000/4000 SeriesTM Product Families and TC10® Transmissions

Background:
The Calibration Support Desk at Allison Transmission frequently receives requests for assistance with cases
involving vehicles with missing Electronic Control Units (ECUs)/Transmission Control Modules (TCMs),
ECUs/TCMs that will not communicate, or ECUs/TCMs with incorrect calibrations. Proper calibration settings are
necessary for correct vehicle operation. This Tech Tip describes a set of steps that are available to the service
technician to determine the correct TCM calibration settings.
Previously, the Missing CIN Form was used to request a new calibration for an existing vehicle with an unknown
calibration. The Missing CIN Form will no longer be used.

Service Procedure:
A. Controls Systems Prior to Allison 5th Generation Controls:
1. Determine the most recent calibration settings loaded into the ECU or TCM as follows:
a. If the current TCM is available and will communicate, use Allison DOC® to retrieve the Calibration
Identification Number (CIN) or “Cal ID”. Proceed to Paragraph A.2 for instructions regarding
the loading of the calibration.
b. If the current TCM is available and will NOT communicate, enter the ECU or TCM serial number
into the ECU/TCM Number field of Allison Unit History on the Allison Extranet to determine if the
prior load track history is available for the ECU or TCM. Refer to Figure 1 and Figure 2.
NOTE: For WTEC II and WTEC III TCMs, the TCM S/N entry into Allison Unit History must be eight (8)
characters in length. If the S/N on the ECU/TCM is shorter, add 0’s to the beginning of the S/N until it is
8 characters in length.
i. The ECU/TCM assembly number can be found on the ECU/TCM search results page. Refer to
Figure 2.
ii. If the ECU/TCM assembly number field is not populated, combine the Manufacturer Hardware
Number and Calibration Sequence Number, if available, to determine the ECU/TCM Assembly
number. Refer to Figure 2.
• If the Calibration Sequence Number is available, but the Manufacturer Hardware Number
is unavailable, add "TCM" before the Calibration Sequence Number to make up the

JC

3573203

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1000/2000 Series Pre­4th Generation TCM Assembly Number. Add "ECB" when using
the WTEC III service ECU or "A59" when using the 4th Generation A59 service TCM.
i. After determining the ECU/TCM assembly number, proceed to Paragraph A.2.
ii. If an ECU/TCM assembly number cannot be determined, proceed to the Support section at
the end of this Tech Tip.

Figure 1. Allison Unit History – ECU/TCM Search

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Figure 2. Allison Unit History – ECU/TCM Search Results
c. If the current ECU/TCM is NOT available, use the transmission serial number to determine whether
an ECU or TCM serial number has been associated with the transmission.
i. Enter the transmission serial number into the Allison Unit History Serial Number field. Refer
to Figure 3 and Figure 4.
ii. If available, click the Related Serial Number link to determine the ECU or TCM Assembly
Number, or enter the ECU/TCM serial number into the Allison Unit History ECU/TCM Number
Search as described in Paragraph A.1.b.

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Figure 3. Allison Unit History – Transmission Serial Number Search

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Figure 4. Allison Unit History – Transmission Serial Number Search Results
NOTE: Use the ECU/TCM Calibration Load Date field to determine the most recent calibration if more
than one ECU/TCM S/N is available.
iii. If an ECU/TCM assembly number is found, proceed to Paragraph A.2.
iv. If an ECU/TCM assembly number cannot be determined, proceed to the Support section at
the end of this Tech Tip.
2. If the latest calibration was determined in Paragraph A.1, review the calibration information to determine
if it is appropriate for the vehicle/transmission configuration.
a. Use Allison TCM ReflashTM to view the Calibration Summary Report. In Allison TCM ReflashTM,
select Add, enter the CIN or TCM Assembly Number, and select the View Summary Report button.
b. If the calibration settings are appropriate for the vehicle/transmission, load the calibration into the
TCM using Allison TCM ReflashTM.
c. If there is uncertainty that the calibration settings are appropriate for the specific vehicle or
ECU/TCM, stop and proceed to the Support section at the end of this Tech Tip.
d. The CIN may require an updated version for loading into the service ECU/TCM. Use the following
methods to update the CIN:
i. WTEC II – Convert a CIN beginning with 07 to an updated CIN beginning with 08 by replacing
the 07 with 08 and by increasing the last digit of the CIN by 1 digit. For instance, if the current
CIN is 07­00152­003­J, the J increases by 1 digit to a K. New CIN 08­00152­003­K can be
used. (The letters I and O are not used in CINs, so those letters should be skipped. The order
of the last digit is 0,1,2,3,4,5,6,7,8,9,A,B,C,...Y,Z,0,1,2 etc.)
ii. WTEC III – Convert ECU Assembly Number from ECA0abcd to ECB0abcd or convert the
CIN from 0w0abcd0xyz to TCM Assembly Number ECB0abcd.

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iii. 4th Generation Controls – Convert TCM Assembly Number from A41, A42, A43, A51, A52,
or A530abcd to A590abcd or convert the CIN from 4w0abcd0xyz to TCM Assembly Number
A590abcd.
NOTE: If an error message is received in Allison TCM ReflashTM, please send the original CIN to
[email protected] to request assistance.
B. Allison 5th Generation Controls System:
1. Determine the most recent calibration settings loaded into the TCM.
a. If the current TCM is available, enter the TCM serial number into the ACCT Summary Report tool to
determine if the calibration is available in the Allison calibration database. Refer to Figure 5 and
Figure 6. The TCM serial number can be found on the label of the TCM or by connecting to the
TCM with the Allison DOC®.
i. If a calibration summary report does not exist for the TCM serial number, enter the vehicle
identification number (VIN) or transmission serial number to determine if a calibration summary
report is available for the VIN or transmission.
ii. If the TCM, VIN, and transmission are not found in ACCT, and if communications are possible
with the TCM, follow the steps in Tech Tip TT7583 to upload TCM calibration information
using Allison DOC®. Then re­enter the TCM serial number into ACCT to obtain the calibration
summary report.
NOTE: ACCT is located in the Engineering section of the Allison Extranet (https://
sap.allisontransmission.com/extranet/acct/app/Dashboard.action).
If ACCT is not available in the Allison Extranet Engineering menu, contact the Calibration Support Desk
([email protected]) to request access.

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Figure 5. ACCT Dashboard

Figure 6. Summary Report Request Screen
b. If the current TCM is unavailable, enter the vehicle identification number or transmission serial
number into ACCT to determine if a calibration summary report is available as described in
Paragraph B.1.a.i. Refer to Figure 5 and Figure 6.
c. If a calibration summary report is available using one of the prior methods, proceed to Paragraph
B.2.
d. If a calibration is still not found, proceed to the Support section at the end of this Tech Tip.

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2. If the latest calibration summary report is available, review all calibration settings on the report to
determine if the calibration is appropriate for the vehicle and transmission configuration. Refer to
Figure 7.
a. If the calibration settings are appropriate for the vehicle and transmission, use Allison TCM
ReflashTM to load the calibration using the TCM serial number.
b. If there is uncertainty that the calibration settings are appropriate for the specific vehicle or TCM,
stop and proceed to the Support section at the end of this Tech Tip.

Figure 7. ACCT Calibration Summary Report

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Support:
If none of the above procedures produce an ECU or TCM calibration:
• Request the original calibration for the vehicle by contacting the OEM or the Allison Calibration Support Desk
([email protected]).
• Provide the VIN, OEM information, transmission serial number, and define the request as a “Missing
Calibration”.
NOTE: If a calibration is provided, it will match the OEM’s original factory settings and will not include
any changes made after the vehicle entered into service. Transmission and vehicle operation must
be confirmed after loading the factory settings.
• If all other attempts have proven unsuccessful, a new calibration may be configured. Additional information,
including engine make/model/rating, etc. may be required to properly configure the calibration.
To request a new calibration, locate the Recalibration EMAIL Request Form in the Service section of the Allison
Extranet. Go to the “Forms and Guides” section of the Allison TCM ReflashTM page within the Service menu
(https://hub.allisontransmission.com/app/allison­tcm­reflash). Complete the Recalibration EMAIL Request Form
and submit to Allison Calibration Support ([email protected]).
For Allison calibration support, email [email protected] or contact the Technical
Assistance Center (TAC) at 1­800­252­5283.

Copyright © 2017 Allison Transmission, Inc. All Rights Reserved.