Service Bulletin

21-021

July 29, 2021

Version 3

MIL Comes On with DTC U0155
Supersedes 21-021, dated June 24, 2021, to revise the information highlighted in yellow.
AFFECTED VEHICLES
Year

Model

Trim Level

VIN Range

2021

Accord

ALL

1HGCV1…MA000001 thru 1HGCV1…MA052042
1HGCV2…MA000001 thru 1HGCV2…MA015972

2021

Accord Hybrid

ALL

1HGCV3…MA000001 thru 1HGCV3…MA018131

2021

HR-V

EX, EX-L

3CZRU5…MM700001 thru 3CZRU5…MM729140
3CZRU6…MM700001 thru 3CZRU6…MM744103

2022

Odyssey

ALL

5FNRL6…NB000001 thru 5FNRL6…NB008406

REVISION SUMMARY
Under AFFECTED VEHICLES, VIN range was revised.
Under POSSIBLE CAUSE, new information was added.
SYMPTOM
The MIL comes on with DTC U0155 (Lost Communication with Gauge Control Module).
POSSIBLE CAUSE
During certain conditions after conducting an evaporative emission leak check, a mismatch in control module shutdown
commands results in the DTC being set. Also, if you rapidly press the ENGINE START/STOP button during engine
cranking, that may result in the DTC being set.
CORRECTIVE ACTION
Update the PGM-FI software.
WARRANTY CLAIM INFORMATION
The normal warranty applies.
Operation
Number

Description

Flat Rate
Time

Defect
Code

Symptom
Code

Template
ID

Failed Part Number

1255D8

Update the PGM-FI
software.

0.2 hr

03214

03217

A21021A

37805-6A0-A93

Skill Level: Repair Technician

CUSTOMER INFORMATION: The information in this bulletin is intended for use only by skilled technicians who have the proper tools, equipment,
and training to correctly and safely maintain your vehicle. These procedures should not be attempted by “do-it-yourselfers,” and you should not
assume this bulletin applies to your vehicle, or that your vehicle has the condition described. To determine whether this information applies, contact
an authorized Honda automobile dealer.

© 2021 American Honda Motor Co., Inc. – All Rights Reserved

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SOFTWARE INFORMATION
NOTE: Unnecessary or incorrect repairs resulting from a failure to update the diagnostic and reprogramming software are
not covered under warranty.
Before beginning the repair, make sure all diagnostic and reprogramming software are updated as listed.
i-HDS Software Version

1.006.026 or later

HDS Software Version

3.104.014 or later

J2534 Rewrite Software Information
PC Application Version

1.2.1.1

Database Update

16-JUN-2021 or later

NoticeDB Version

16-JUN-2021 or later

Update only the systems and software listed in this service bulletin.
American Honda has validated and approved the Denso DST-I as the vehicle communication interface (VCI) to
support this service bulletin.
For more information about updating vehicle systems, refer to service bulletin 01-023, Updating Control Units/Modules.
Year/Model

Vehicle System

Program ID (or later)

2021 Accord LX

PGM-FI

37805-6A0-A930

2021 Accord Sport

PGM-FI

37805-6A0-AF30

2021 Accord Sport (Special Ed.)

PGM-FI

37805-6A0-CG30

2021 Accord EX-L

PGM-FI

37805-6A0-AG30

2021 Accord Sport (2.0 L)

PGM-FI

37805-6B2-A940

2021 Accord Touring (2.0 L)

PGM-FI

37805-6B2-C540

2021 Accord Hybrid LX, EX, EX-L

PGM-FI

37805-6C2-A540

2021 Accord Hybrid Touring

PGM-FI

37805-6C2-A640

2021 HR-V EX, EX-L (2WD)

PGM-FI

37805-51M-AC20

2021 HR-V EX, EX-L (AWD)

PGM-FI

37805-51M-AF20

2022 Odyssey

PGM-FI

37805-5MR-C920

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REPAIR PROCEDURE
NOTE:
• Make sure the 12-volt battery is fully charged before starting an update.
• Connect a fully charged jumper battery to the vehicle, and leave it connected during the entire procedure to maintain
steady voltage.
• Do not use the GR8 because the vehicle requires a steady electrical current.
• Control module failure caused by the improper completion of a software update (early key cycle, low battery voltage,
disconnected DLC cable, etc.) is not covered by warranty.
• If an error occurs during the update or the i-HDS freezes, do not disconnect the battery or turn the ignition to OFF.
Reboot the i-HDS, and start over.
• To prevent control unit damage, do not operate anything electrical (headlights, audio system, brakes, A/C, power
windows, door locks, etc.) during the update.
• Warranty reimbursement for technician labor is not allowed for routine checking/installation of any available software
update.
1. Update the PGM-FI software using the J2534 Rewrite software with the DST-i. Refer to service bulletin 01-023,
Updating Control Units/Modules.
NOTE: This update does not require entering a service bulletin number
2. Delete any DTCs.
END

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