Subject:

Engineering Information - (MIL) on (DIC), BET and BEV3 Ultium Packs Setting Moving Average Voltage Detection
(MAVD) and Delta Voltage Rest Period (DVRP) Fault Codes, DTC’s U3620, U3621, U3622, U3623, U3624, U3625,
U3626, U3627, U3628, U3629, U362A, U362B, U362C, U362D, U362E, U362F, U3630, U3631, U3632, U3633, U3634,
U3635, U3636, U3637, U3638, U3639, U363A, U363B, U363C, U363D, U363E, U363F, U2B7A, U2B7E, U2B98, U2B82,
U2B86, U2B8A, U2B8E, U2B92, U2B96, U2B99, U2B9A, U2B9B, U2B9C, U2B9D, U2B9E, U2B9F Set

Attention:

Proceed with this EI ONLY if the customer has commented about this concern AND the PIE number is listed in the
Global Warranty Management / Investigate History link (GWM/IVH). If the customer has not commented about this
condition or the EI does not show in GWM/IVH, disregard the PIE, and proceed with diagnostics found in published
service information. THIS IS NOT A RECALL refer to Service Bulletin 04-00-89-053 for more details on the use of
Engineering Information bulletins.

This EI has been revised to updated Subject and added Additional Keywords. Please discard PIE0788.
Brand:

Model:

Model Year:

VIN Breakpoint:

from

to

from

to

Zevo 600

2023

2024

—

—

Zevo 400

2024

Cadillac

LYRIQ

2023

Chevrolet

Blazer EV

2024

BrightDrop

Engine:

Transmission:

—

—

Equinox EV
Silverado EV
GMC

HUMMER EV

2022

HUMMER EV SUV

2024

Involved Region or Country

U.S. Dealers ONLY

Condition

Some customers may comment on the Malfunction Indicator Lamp (MIL) illuminated on the Driver
Information Center (DIC).
Technicians may find one or more of the following DTCs set.
U3620, U3621, U3622, U3623, U3624, U3625, U3626, U3627, U3628, U3629, U362A, U362B, U362C,
U362D, U362E, U362F, U3630, U3631, U3632, U3633, U3634, U3635, U3636, U3637, U3638, U3639,
U363A, U363B, U363C, U363D, U363E, U363F, U2B7A, U2B7E, U2B98, U2B82, U2B86, U2B8A, U2B8E,
U2B92, U2B96, U2B99, U2B9A, U2B9B, U2B9C, U2B9D, U2B9E, U2B9F

Cause

GM Engineering is attempting to determine the root cause of the above condition. Engineering has a need to
gather information on vehicles PRIOR to repair that may exhibit this condition. As a result, this information will
be used to "root cause" the customer's concern and develop/validate a field fix.

Correction
Important: This engineering information (PIE) can only be completed by certified repair facilities who have met all specific training, tool and equipment
requirements pertaining to the vehicle Brand and Model serviced. Repairs must be performed by a technician who has successfully completed the required
training.
Important: Service agents must comply with all International, Federal, State, Provincial, and/or Local laws applicable to the activities it performs

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under this bulletin, including but not limited to handling, deploying, preparing, classifying, packaging, marking, labeling, and shipping
dangerous goods. In the event of a conflict between the procedures set forth in this bulletin and the laws that apply to your dealership, you must
follow those applicable laws.
If you encounter a vehicle with the above concern, perform the following and contact one of the engineers listed below with your findings:
Important: DO NOT clear the codes or program the BECM and make sure 12-volt battery is charged.
1.

Is the Malfunction Indicator Lamp (MIL) currently illuminated on (DIC)?

2.

Did the customer experience the (MIL) immediately after DCFC charging?
2.1. If no, describe the drive trip prior to the (MIL) being illuminated on the (DIC).

3.

What type of home charger does the customer typically use? (Make/Model/KW capability)

4.

What is the DTC/SYM Byte setting?
4.1. Current or History?

5.

Did the vehicle come in with a dead 12V battery?
5.1. Has the 12V battery or HVSL been disconnected during this visit?

6.

Has the vehicle been programmed?

7.

Provide the current BECM CAL information. The BECM CAL can be found in GDS2 - Module Diagnostics - K16 BECM – Identification Information –
Identification Information - Calibration Part Number 1.

8.

Were any codes cleared?

Contact Information

The Contact Information has been redacted.

Please include the following information if leaving a message:
–

Technician name

–

Dealer name and phone number

–

Complete VIN and repair order (R.O) number

On the repair order, document the date and time the call was placed (even if the engineer was not reached).
If engineering is unable to return the call within one hour, proceed with diagnosis and repair based on information found in SI.

Warranty Information
If an engineer was contacted or required information was provided, use:
Labor Operation

Description

Labor Time

2887598*

Engineering Information - (MIL) Illuminated on (DIC), Multiple DTC’s Set

0.5 Hrs.

Add

Additional Cycling/Tests if Instructed

1.5 Hrs.

*This is a unique Labor Operation for bulletin use only.

Version

2

Modified

Released April 30, 2024
Revised May 07, 2024 – Updated Subject and added Additional Keywords.

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Additional Keywords: U3620, U3621, U3622, U3623, U3624, U3625, U3626, U3627, U3628, U3629, U362A, U362B, U362C, U362D, U362E, U362F, U3630,
U3631, U3632, U3633, U3634, U3635, U3636, U3637, U3638, U3639, U363A, U363B, U363C, U363D, U363E, U363F, U2B7A, U2B7E, U2B98, U2B82,
U2B86, U2B8A, U2B8E, U2B92, U2B96, U2B99, U2B9A, U2B9B, U2B9C, U2B9D, U2B9E, U2B9F

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