Bulletin No.: PIT6044F
Published date: 12/1/2023

Preliminary Information
PIT6044F Service High Voltage with MIL and/or DTCs
Models
Brand:

Model:

Model Years:

VIN:
from

to

Engine:

Transmissions:

BrightDrop

Zevo 600 eLCV

2023

ALL

All

All

All

Cadillac

EV LYRIQ

2023 - 2024

ALL

All

All

All

GMC

HUMMER EV

2022 - 2024

ALL

All

All

All

GMC

HUMMER EV SUV

2024

ALL

All

All

All

Involved Region or Country North America

Condition

Some customers may comment the MIL is illuminated or Service High Voltage
Message displayed on the IPC.
A technician may nd any of the following DTCs; U2220, U2221, U2222, U2223,
U2224, U2225, U2226, U2227, U2228, U2229, U222A, U222B, U222C, U222D, U222E,
U222F, U2230, U2231, U2232, U2233, U2234, U2235, U2236, U2237, and/or U2C11
set as current or history.

Cause

A potential software anomaly may be present.

Correction:
1. Verify the vehicle has one or more of the following DTCs set; U2220, U2221, U2222, U2223, U2224, U2225,
U2226, U2227, U2228, U2229, U222A, U222B, U222C, U222D, U222E, U222F, U2230, U2231, U2232, U2233,
U2234, U2235, U2236, U2237, and/or U2C11 set as current or history.
Note: If all Loss of Communication DTCs are set U2220-U2237 as current or history (depending on vehicle
application), do not continue with the procedure. Please start a TAC case and reference this P.I.
2. Perform the Battery Negative Cable Disconnection and Connection procedure outlined in Service
Information.
Warning: Always ensure the Battery Maintenance Mode is inactive before disconnecting the 12volt battery. This mode can be active with the ignition o , regardless of whether the vehicle
charging cord is plugged in or not. When this mode is active, the on-board high voltage battery
charger will energize the 12-volt battery cables and charge the 12-volt battery. Disconnecting the
battery cables while this mode is active may result in an electrical shock or a burn from hot
battery cable leads.
3. Wait 15 mins, then reconnect the 12v following the Battery Negative Cable Disconnection and Connection
procedure outlined in Service Information.
4. Place the vehicle in Propulsion “Ready” mode, then turn the vehicle “OFF” and remove the keyless
transmitter from the vehicle and place the transmitter in a safe location approximately 10 ft away. Wait 15
mins. Perform this two times.
5. Place the vehicle in Service mode and use GDS2 and clear all DTCs.

If any of the following DTCs: U2220, U2221, U2222, U2223, U2224, U2225, U2226, U2227, U2228, U2229,
U222A, U222B, U222C, U222D, U222E, U222F U2230, U2231, U2232, U2233, U2234, U2235, U2236, U2237,
and/or U2C11 return, start a TAC case, and reference this P.I.
6. After completing steps 1-5 above, program the K16 BECM (Battery Energy Control Module) as outlined in
Service Information.
7. After programming the BECM, perform the Battery Negative Cable Disconnection and Connection
procedure outlined in Service Information / steps 2 & 3 above 1 time.
8. Verify no DTCs are set.
If any of the following DTCs: U2220, U2221, U2222, U2223, U2224, U2225, U2226, U2227, U2228, U2229, U222A,
U222B, U222C, U222D, U222E, U222F U2230, U2231, U2232, U2233, U2234, U2235, U2236, U2C11 and/or U2237
return, start a TAC case, and reference this P.I.

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
5080388
Add Time (as Required)

Description
Labor Time
Hybrid/Electric Vehicle Battery Pack Communication
1.5 Hr.
Module manual reset
K16 Battery Energy Control Module Program
0.4 Hr.
*This is a unique Labor Operation for Bulletin use only

Version History
Version

7

Modi ed

08/03/2023 - Created on.
08/09/2023 - Updated to include U2C11
09/01/2023 - Updated to add more information for the LYRIQ
09/05/2023 - Update more programming numbers for 2024 LYRIQ
10/26/2023 - Update information for BrightDrop and HUMMER EV
10/30/2023 - Updated correction.
12/01/2023 - Updated correction.

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