Bulletin No.: PIT6394E

Service Bulletin

Date: March, 2026

PRELIMINARY INFORMATION
Subject:

Brand:

Service Driver Assist Message- B233B Long Range Radar Module Will Not
Complete Learn
Model:

Model Year:
from

VIN:
to

from

Engine:

Transmission:

to

Buick

Enclave

2025-2026

ALL

ALL

ALL

ALL

Buick

Envision

2024-2026

ALL

ALL

ALL

ALL

Cadillac

CELESTIQ

2025

ALL

ALL

BEV

ALL

Cadillac

CT5

2025-2026

ALL

ALL

ALL

ALL

Cadillac

Escalade

2025-2026

ALL

ALL

ALL

ALL

Cadillac

Escalade
ESV

2025-2026

ALL

ALL

ALL

ALL

Cadillac

ESCALADE
IQ

2026

ALL

ALL

BEV

ALL

Cadillac

LYRIQ

2023-2026

ALL

ALL

BEV

ALL

Cadillac

OPTIQ

2025-2026

ALL

ALL

BEV

ALL

Cadillac

VISTIQ

2026

ALL

ALL

BEV

ALL

Cadillac

XT4

2023-2025

ALL

ALL

ALL

ALL

Chevrolet

Blazer EV

2024-2026

ALL

ALL

BEV

ALL

Chevrolet

BrightDrop
400

2023-2026

ALL

ALL

BEV

ALL

Chevrolet

BrightDrop
600

2023-2026

ALL

ALL

BEV

ALL

Chevrolet

Equinox

2025-2026

ALL

ALL

ALL

ALL

Chevrolet

Equinox EV

2024-2026

ALL

ALL

BEV

ALL

Chevrolet

Silverado EV

2024-2026

ALL

ALL

BEV

ALL

Chevrolet

Suburban

2025-2026

ALL

ALL

ALL

ALL

Chevrolet

Tahoe

202-20265

ALL

ALL

ALL

ALL

Chevrolet

Traverse

2024-2026

ALL

ALL

LK0

ALL

GMC

Acadia

2024-2026

ALL

ALL

ALL

ALL

GMC

Sierra EV

2024-2026

ALL

ALL

BEV

ALL

GMC

Terrain

2025-2026

ALL

ALL

ALL

ALL

GMC

Yukon

2025-2026

ALL

ALL

ALL

ALL

GMC

Yukon XL

2025-2026

ALL

ALL

ALL

ALL

Involved Region or Country

North America

Additional Options (RPO)

UGN

Copyright 2026 General Motors. All Rights Reserved.

Page 2

March, 2026

Bulletin No.: PIT6394E

Condition

A vehicle may have a Service Driver Assist Message.
Code U3000 SYM 78 may be set.
When attempting to learn the B233B Long Range Radar Module (LRRM) it will time out
and not complete.
When attempting to restart the learn procedure a message "conditions not met" may be
found on the GDS2 screen.

Cause

Due to a new type of Long Range Radar being used the criteria to complete the learn has
changed.
In the past driving on a highway or two lane road with vehicles to follow was ideal but this
is not true for this type of radar.

Correction
Use the scan tool to enable the LRRM learn procedure following the steps in SI or on the scan tool.
Drive the vehicle in a city or urban type environment.
While it is ideal to continue moving, if stops are encountered it will not end the process, it will simply slow it down.
To complete the calibration, it helps if the radar detects multiple vehicle types, varying vehicle size, shape and height
will help trigger the necessary detections.
Following distance is also important. A following distance behind vehicles of 50-150 feet is best.
The radar must also detect stationary roadside objects that are close to the edge of the road.
Objects that can help include Mailboxes, Guardrails, Parked vehicles, Construction zones, Trees and Buildings near
the roadway.
Oncoming traffic can also help.
Below are situations that will prevent learning
No Objects or Vehicles.

6975451

Objects Too Far Away

Bulletin No.: PIT6394E

March, 2026

Page 3

6975452

Stationary Objects Too Small

6975455

Below are situations that are good for learning.
Variety of Different Sized Vehicles.
Oncoming vehicles.

Page 4

March, 2026

Bulletin No.: PIT6394E

6975456

Multiple Stationary Objects Near Road

6975457

Azimuth angle will increment up to 100%.
Elevation angle will not give any indication that it is completing. It will show" Incomplete" until it suddenly goes to
"Complete".
If the procedure times out before completing the calibration, the status will change from "learn in progress" to "Error".
This indicates that the module attempted to calibrate but did not detect all of the required conditions to successfully
complete.

Bulletin No.: PIT6394E

March, 2026

Page 5

If GDS displays a "loss of communication" message or an "error" message during the learn procedure using the
scan tool, navigate to B233B Forward Range Radar Sensor> Data Display> Calibration history> Learn status.
If the learn status shows in progress continue to drive the vehicle to complete the calibration. Do not click "learn"
again.
If the vehicle has been driven several times and the learn will not complete there is a reset button in GDS. Ensure
the vehicle is still in learn mode following the direction above and with the vehicle below 6 mph use the reset to start
the learn over again.
Note: This should only be used as a last resort as any progress that has been made will be erased and you will be
starting the procedure over again.
It is imperative that the vehicle be driven in this environment, the learn will not complete if driven on roads that
worked well in the past to perform a learn.

Warranty Information
For vehicles repaired under the Bumper-to-Bumper coverage (Canada Base Warranty coverage), use the following
labor operation. Reference the Applicable Warranties section of Investigate Vehicle History (IVH) for coverage information.
Labor
Operation
2880398*

Description

Labor Time

Long Range Radar Learn
Tips - This is to be used
with the learn procedure
time, not instead of it.

0.3 Hr.

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

Version

5

Modified

06/05/25 - Created on.
06/30/25-Updated to add photos and additional tips.
08/07/2025 - Updated Models and Correction.
02/17/26-Updated to add Envision and update to model year 2026
02/26/26- Updated to correct errors in model years on previous version
03/05/26- Updated to correct errors in model years from previous version.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job
properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.

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