GROUP

NUMBER

HYBRID CONTROL
DATE

Technical Service Bulletin
SUBJECT:

23-HC-001H
MODEL(S)

JUNE 2023

SONATA HYBRID
(YF HEV)

HYBRID POWER RELAY DTC P1B25, P1B76, P1B77, P0A0D

This TSB supersedes TSB# 14-HC-002-1 to revise the Service Procedure and applicable
vehicles.
Description: On certain Sonata hybrid (YF HEV) vehicles, the HEV safety plug or power relay assembly
(PRA) may cause the following symptoms and one or more current related DTCs. Follow the Service
Procedure before diagnosing the hybrid battery. Please review the following instructions carefully to
determine applicability depending on the model year of your vehicle.
Warning light:
• No “EV Ready” mode, or “Ready” light blinks on and off
• “Check Engine” warning light on
• Charging system warning light on
• “Wrench” symbol (service indicator) blinks on and off
Drivability symptoms:
• Vehicle will not move from a stop or gasoline engine will not turn on.
• Warning in the instrument cluster display: “Hybrid System Warning! Safely stop and Do Not
Drive” and/or alarm sound.
DTC List:
DTC

Description

Inspect

P0A0D

High Voltage System Interlock Circuit High

HEV safety plug

P1B25

High Voltage Path Fault

HEV safety plug

P1B76

High Voltage Relay Fault

Power relay assembly

P1B77

High Voltage Precharging Fault

Power relay assembly

For 2013-2015MY Sonata Hybrid (YF HEV): Please refer to “TSB 23-01-XXXH Safety Plug and Fuse
Inspection/Replacement (Service Campaign 994)” first if open on the vehicle before troubleshooting
Power Relay Assembly (PRA). If no open campaigns are found, proceed with this TSB.

Applicable Vehicles: 2011-15MY Sonata Hybrid (YF HEV)

Circulate To: General Manager, Service Manager, Parts Manager, Warranty Manager, Service
Advisors, Technicians, Body Shop Manager, Fleet Repair

HYBRID POWER RELAY DTC P1B25, P1B76, P1B77, P0A0D

SUBJECT:

Parts Information:
Model

Part Name

Section

2011-15MY
Sonata Hybrid
(YF HEV)

Power Relay Assembly
(PRA)

PNC

Part Number

37514

37514-4R000

37586

37586-4R000AS
37586-4R002
*Refer to parts
catalog for the
applicable safety
plug P/N

37-371
2011-15MY
Sonata Hybrid
(YF HEV)

SST Information:
Tool Name

EV Safety Plug

Figure

Electrical Insulating
Safety Glove/Protector
Set*

Tool #

Remarks

J-48755-10H (small)
J-48755-11H (medium)
J-48755-12H (large)

Order from
Hyundai.servicesolutions.com,
“EV Tools”

*Use only rubber insulating gloves that meet or exceed ASTM D120 standards (1000 volts AC/1500
volts DC).
Warranty Information:
Model

Op. Code

Operation

Op.
Time

Causal Part

All Sonata
Hybrid
(YF HEV)

37514R1H

Power Relay Assembly
Replacement

1.0
M/H

37514-4R000

37586R1H

Safety Plug Inspection &
Replacement

0.2
M/H

37586-4R001

37514RQ0

GDS operation

0.3
M/H

N/A

2011-2012
Sonata
Hybrid
(YF HEV)

Nature
Code

Cause
Code

E23

ZZ6

NOTE 1: Normal warranty applies.
NOTE 2: Submit claim on Claim Entry Screen as “Warranty” type.
NOTE 3: All claims must follow the Digital Documentation Policy for VIN, Mileage and Part validation.
Claims submitted that have incomplete, illegible, or missing documentation are subject to
debit.
NOTE 4: The incident parts are subject to callback through the normal Warranty Technical Center
(WTC) parts return process. Claim is subject to debit if the parts requested are not returned.
NOTE 5: If a part is found in need of replacement while performing this TSB and the affected part is
still under warranty, submit a separate claim using the same repair order. If the affected part is out of
warranty, submit a Prior Approval request for goodwill consideration prior to performing the work.
TSB #: 23-HC-001H

Page 2 of 10
SUBJECT:

HYBRID POWER RELAY DTC P1B25, P1B76, P1B77, P0A0D

SUBJECT:

STUI
As outlined in the Digital Documentation Policy, all claims require VIN and Mileage validation
through VCI connection or photo capture, AND photo capture of the repair Part according to the
steps in the TSB. All claims submitted that have incomplete, illegible, or missing
documentation are subject to debit.
Service Procedure:
1.

If vehicle is 13-15MY, go directly to step 7 for Power Relay Assembly Replacement.

2.

Depress the brake pedal and press the Start/Stop button once to activate “EV Ready” mode.
Attach a GDS, and select VIN, BMS menu and DTC. Check for DTC in the BMS menu. Record
the DTC and description. Delete the DTC.
Select Current Data and the following parameters. If the results are not as shown, the power
relay assembly (PRA) may not be functioning correctly. Go to step 3.

3.

Parameter
BMS Main Relay ON Status

Result
YES

Inverter Capacitor Voltage

200v~310v

Turn off the ignition, open the rear trunk and
open the cover to the safety plug.
!

WARNING

Failure to wear protective gear and perform
this procedure may result in accidental
injury or death.
Follow all safety precautions in the shop
manual:
• Hybrid Motor System > General Safety
Information and Caution
Put on insulating gloves and pull up on the
black tab and pull out the safety plug.
4.

Without depressing the brake pedal, push the Engine Start-Stop button 2 times to power the
cluster.
Attach a GDS and select BMS menu, Current Data and Inverter Capacitor Voltage.
Confirm the Inverter Capacitor Voltage is less than 30V.
• If less than 30V, the system voltage is safe for the technician. Turn OFF the ignition and
disconnect the 12V negative (–) battery cable. Go to step 4.
• If more than 30V, wait until the voltage is less than 30V before performing any repairs.
Turn OFF the ignition and disconnect the 12V negative (–) battery cable. Go to step 5.

TSB #: 23-HC-001H

Page 3 of 10
SUBJECT:

SUBJECT:

5.

HYBRID POWER RELAY DTC P1B25, P1B76, P1B77, P0A0D

Use a DVOM to measure the resistance of the
BUS fuse inside the safety switch.
Measure the resistance between the BMS
pins.
Specification: 1Ω or less
BUS
Fuse

If the resistance is:
•
•

Not within specification: Replace the
safety plug and proceed to step 7.

BMS