NHTSA ID Number: 10137310
Manufacturer Communication Number: 18NA084
TSB/Document Date: 2018-05-21
Summary
This Bulletin provides information for High Voltage Battery
Disconnect Relay Replacement (Also known as A28 Hybrid/EV Battery Contactor Assembly) to correct the No/Start and DTCs P0AA1 and P0AA4 condition.
If the PDF is very large, it may not load in the preview below.
Some older TSBs had multiple PDFs — visit the NHTSA Website to view all PDFs.
If the TSB PDF does not show, download or view it on the NHTSA Website.
Click on the (+) Plus Sign
Then Click on Associated Document(s)
- 💝【Questions? We’re Here Anytime】MK808S is a...
- 🔥🔥🔥【2026 NEWLY RELEASED BI-DIRECTIONAL...
- 【28+ MOST POPULAR RESET SERVICE FOR 150 MAKES】Autel...
- 【ALL SYSTEM DIAGNOSTICS, FACTORY-LEVEL SCANNER】The...
- 【AUT0 SCAN & AUT0V1N, 10X FASTER】How much have you spent...
- 💯【Conta.ct us for Support Directly】If you met any...
- 🔥🔥🔥【2026 AUTEL FLAGSHIP MK900BT MK900-BT, NEW...
- 🚗【3000+ ACTIVE TESTS (50➡3000+), SAME AS MS...
- 🚗【40+ HOT SERVICES FOR 150 MAKES (28+➡40+)】Full...
- 🚗【OE ALL SYSTEM DIAGNOSE, AUTO SCAN 2.0: SCAN LICENSE...
This product presentation was made with AAWP plugin.
Search NHTSA Database for Recalls
Search NHTSA Database for Vehicle Investigations
View Latest Vehicle Investigations
Search NHTSA Database for Vehicle Complaints
View Latest Vehicle Complaints
TSB/Document ID: 18NA084
Replacement Service Bulletin Number:
MFR Communication Date: 2018-03-15
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ELECTRICAL SYSTEM:12V/24V/48V BATTERY
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
File in Section:
-
Bulletin No.:
Service Bulletin
18-NA-084
Date:
March, 2018
TECHNICAL
Subject:
Hybrid Unable to Start in Cold Temperatures, MIL Illuminated, DTC P0AA1 and/or
P0AA4 Set
Brand:
Model:
Malibu
(VIN Z)
Model Year:
VIN:
from
to
from
to
2016
2016
—
—
Engine:
1.8L (RPO
LKN) — (Hybrid
RPO HP4)
5ET50
(RPO MKE)
Involved Region or Country
United States and Canada
Condition
Some customers may comment that the vehicle is unable to start in cold temperatures
and the Malfunction Indicator Lamp (MIL) is illuminated.
Cause
One or both of these contactors, the Battery Positive Contactor or the Battery Negative
Contactor in the High Voltage Battery Disconnect Relay (also identified as the A28
Hybrid/EV Battery Contactor Assembly) may stick closed as a result of cold ambient
temperatures, causing the No/Start condition and the DTC or DTCs to set.
Some technicians may find one or both of the following DTCs set in the K114B Hybrid
Powertrain Control Module 2 (HPCM2):
• DTC P0AA1 Hybrid/EV Battery Positive Contactor Circuit Stuck Closed
• DTC P0AA4 Hybrid/EV Battery Negative Contactor Circuit Stuck Closed
Correction
A design change has been made to the contactors in the High Voltage Battery Disconnect
Relay to address this cold weather contactor sticking condition. Replace the High Voltage
Battery Disconnect Relay with the latest available part.
Service Procedure
1. Vehicle in Service Mode.
2. Verify that DTC P0AD9, P0ADB, P0ADC, P0ADD,
P0ADF, P0AE0, P0AE4, P0AE6, P0AE7 or P1EC0
is not set.
⇒ If any of the DTCs are set, refer to Diagnostic
Trouble Code (DTC) List – Vehicle in SI.
⇒ If none of the DTCs are set, Go to Step 3.
3. Verify that DTC P0AA1 and/or P0AA4 is set
without any of the above Contactor Control
Circuit DTCs.
⇒ If only DTC P0AA1 and/or P0AA4 is set,
replace the High Voltage Battery Disconnect
Relay. Refer to High Voltage Battery
Disconnect Relay Replacement in SI.
Perform the Diagnostic Repair Verification after
completing the repair. Refer to Diagnostic Repair
Verification in SI.
Copyright 2018 General Motors LLC. All Rights Reserved.
Parts Information
Causal
Part
Description
Part
Number
Qty
X
High Voltage
Battery
Disconnect Relay
24284374
1
Warranty Information
For vehicles repaired under warranty, use:
Labor
Operation
Description
Labor Time
5031760
High Voltage Battery
Disconnect Relay
Replacement
Use
Published
Labor
Operation
Time
Page 2
March, 2018
Bulletin No.: 18-NA-084
Version Information
Version
1
Modified
Released March 15, 2018
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.
WE SUPPORT VOLUNTARY
TECHNICIAN
CERTIFICATION
- 🎉[OTOFIX D1 Lite, Perfect Cost-effective Diagnostic Tool]: OTOFIX D1 Lite, a newest bidirectional scan tool from OTOFIX company, is a great choice for DIYers and repair shops. 👉This obd2 scanner diagnostic tool packs all practical functions: OE level all systems diagnoses, Bi-Directional Control, 38+ reset services fixing 99% of common problems, support DoIP & CANDF protocols and FCA
AutoAuth, high-end hardware configuration. Worldwide vehicles and 🔥2 Years Free Updating🔥 covered. - 🎉[Bi-Directional Scan Tool, Active Test]: OTOFIX D1 Lite bluetooth obd2 scanner can also command ECUs and monitor the operation of the actuators to track down the problems of certain parts, like windows, sunroof, wipers, fuel pumps, etc., saving repair time & trouble. This makes OTOFIX D1 Lite the most cost-effective bidirectional scan tool.
- 🎉[2026 Newest, 38+ Hot Reset Functions]: Equipped with 38+ reset functions in one, the OTOFIX D1 lite automotive scanner diagnostic tool allows you to troubleshoot 99% of common vehicle problems. You can use this car diagnostic scanner holding enough functions to easily repair common vehicle models in your repair shops. Including Oil Reset, Injector Coding, Throttle, DPF Reset, SCR Reset, Gear Learning, Clutch Learning, Suspension, etc. Note* Reset functions vary by model.
- 🎉[OE Level Full Systems Diagnostics]: Unlike the 2-system and 4-system diagnostic tools, the OTOFIX auto scan tool can complete comprehensive system diagnostics within 5 minutes. It accesses and scans all available onboard systems like for Engine /AT /ABS /EPB /BMS /TPMS /SRS /SAS /Audio System /BCM /Air Conditioning / etc., to read & clear codes, view live data, and check ECU information. Note: Active test is not involved.
- 🎉[Powerful Hardware Configuration]: Designed with a fashion appearance & a 7” touchscreen and a weight of 463g, this OTOFIX D1 Lite OBD2 diagnostic scanner scan tool is convenient for everywhere and easy to use & store. Android9.0 OS and 2+64GB memory enhance multi-task smoothness and diagnostic operation, no more wasting too much time. 5800mAh battery allows hours-lasting use. WiFi & VCI1 also bring faster communication for your diagnostics.
- 🏆【2026 TOP OBD2 Scanner Diagnostic Tool】OTOFIX D1 Lite wireless obd2 scanner has upgraded hardware configuration and car coverage. The newly upgraded D1 Lite with 🔥OS Android 9.0🔥1.5Ghz 4 core high efficiency processor🔥2GB RAM+64GB ROM large storage🔥5800mAh large battery, more stable and longer lasting diagnostics🔥 38+ Reset🔥action tests🔥full system diagnostic🔥Supports MV105 endoscope🔥21+ Language Supports🔥100000+ vehicle coverage to meet all your daily maintenance needs.
- 👍【Bi-Directional Control / Active Test】D1 Lite obd2 scanner has bidirectional control(worth $300+), which is the most beloved feature among mechanic. If your headlights or car windows are broken, going to a repair shop will cost a lot of money. You can use D1 Lite to send execution commands to the ECU module and identify the repair status. Such as ABS, car windows, doors, valves, wipers, headlights, etc., effectively shorten diagnostic time and reduce diagnostic costs.
- 🔥【All Systems Diagnostics, In-depth Checking】This advanced OBD2 Scanner D1 Lite can perform OE-level diagnosis of all systems including engine, transmission, airbag, ABS, ESP, TPMS, gateway, steering, radio, and air conditioning for more than 100 brands. This diagnostic scanner supports essential functions, such as reading ECU version info, reading and clearing fault codes, and reading data streams.With just a simple click, it provides you with accurate and in-depth diagnostics.
- 🏆【38+ Reset Hot Functions】For repair workshops, holding an OTOFIX D1 Lite Auto scanner is a strong advantage over others. Its 38+ maintenance functions provide various solutions for all module repairs, including Oil Reset, TPMS Reset, Injector Coding, Suspension, Throttle Matching, etc., which will usher your repair business to a new pinnacle. Continuously updating will never make the functionality & compatibility out-of-date.
- 🏆【150+ Models, 10000+ Car Coverage & 16 Languages】D1 Lite is a comprehensive car diagnostic scan tool, help you to troubleshoot car issues fast for 95% US, European, Asian auto makes. ✅ With frequent updates and optimizations allow D1 Lite to cover more vehicles to meet your needs. ✅ Multilingual menu allows auto mechanics around the world to use it without language barriers. 🚩Note: Kindly send us the S/N of the device to authorize new language updates before changing the menu language.
- 【2026 OTOFIX D1 Lite Gives the Best Value for Money】OTOFIX D1 Lite bidirectional scan tool is more FASTER and SMARTER with 2026 Enhanced Hardwares & New Functions! 👍Alternative Bluetooth +USB connect 👍2G+64GB 👍4x ARM Cortex-A35 (1.5GHz) Processor (5X Faster CPU) 👍Android 9.0 OS 👍5G GHz WiFi 👍CANFD&DOIP 👍 FCA AutoAuth 👍38+ Services 👍3K+ Bi-Directional Control 👍Full Systems Diagnose 👍2 Years Update 👍150+ Vehicle Coverage.
- 👍【Active Tests】 OTOFIX D1 Lite is a bi-directional scan tool that can send commands to, and also receive information from vehicle control modules. This way, you can quickly locate and repair faulty auto parts. For Example: send direct commands to ask the vehicle to turn on/off the radiator fan, lights, sound horn, fuel pump, modulate throttle, open/close windows, operate mirrors and more. *Note that only available tests will be displayed in the menu.
- 👍【38+ Service Functions】 OTOFIX D1 Lite scan tool offers 38+ of the hottest service functions that are commonly used for car repairs. That include Oil reset/SAS/EPB/BMS/Throttle/ABS bleeding, and 2065-new SUS/ADBLUE/NOX/Headlamp resets (and more) to help restore your car status after repairs are done. Compared to other diagnostic scanners for cars, the OTOFIX D1 Lite scanner is much more fully-featured. *Note that specific functions available depend on the make/model/year of your car.
- 👍【All System Diagnostics + Cloud Report Management】 This 2026 car scanner OTOFIX D1 Lite provides troubleshooting and data for all ECUs: read/clear DTCs, view graphic live data/VIN, and locate system faults for safe driving. With Cloud Report Management, you can save detailed reports to cloud servers and easily shared them with others via QR codes/emails/text messages. Others can access these reports from any device (smartphones/tablets/PCs …) anytime, and you can better manage repair work.
- 👍【99% Car Coverage】 This one-station car scanner diagnostic for all cars works on 150+ major car brands across the world. 1) It supports CAN-FD/DoIP protocols: compatible with GMCAVALIER/TRAX/Encore/Envision/GL8(LSY)/CT4/CT5 after 2019; Volvo after 2018; Land Rover/Jaguar after 2017; and BM.W F/G all chassis. 2) For models equipped with security modules (such as Renault & 2018+ FCA SGW), its built-in AutoAuth allows you to easily break diagnostic barriers after registration.
This product presentation was made with AAWP plugin.
Last update on 2026-05-11 / Affiliate links / Images from Amazon Product Advertising API