Battery Disconnect Service

This procedure safely disconnects the high-voltage battery system on the 2023 Chevrolet Bolt EUV, including de-energizing the system, removing protective covers, disconnecting electrical connections, and isolating the battery pack from vehicle systems.

Warnings

Tools required

Parts

• High-voltage connector seals (if damaged) × 2 — Use OEM specification
• Coolant (if system opened) × 1 — ACDelco DEX-COOL Orange
• Service disconnect plug cover seal × 1 — Use OEM specification

Fluids

• ACDelco DEX-COOL (Orange) — 2 qt

Preparation

1. Ensure vehicle is parked on level ground with parking brake applied and vehicle in Park mode
2. Turn off all vehicle accessories and remove key fob from vehicle interior
3. Allow battery pack to cool for minimum 2 hours if vehicle was recently driven
4. Verify you have completed manufacturer-approved high-voltage safety training
5. Put on high-voltage safety gloves and have insulated tools ready before beginning work
6. Document battery state of charge from instrument cluster for reference
7. Ensure fire extinguisher rated for electrical fires is nearby

Procedure

1. 1

   Disconnect 12V auxiliary battery
   Open the hood and locate the 12V auxiliary battery in the engine compartment. Disconnect the negative terminal first, then the positive terminal. Remove the battery hold-down and remove the 12V battery from the vehicle. Wait a minimum of 5 minutes to allow high-voltage system capacitors to discharge.
   ⚠Always disconnect negative terminal first to prevent short circuits.
   Torque spec

   Battery Terminal Bolts7 Nm (5 lb-ft)

   Battery Hold-Down Bolt11 Nm (8 lb-ft)
2. 2

   Remove rear seat bottom cushion and access panel
   Remove the rear seat bottom cushion by releasing the front retention clips and lifting upward. Locate the battery service disconnect access panel on the rear floor. Remove the cover screws using a T30 Torx bit to expose the high-voltage service disconnect.
   Torque spec

   Cover Screws11 Nm (8 lb-ft)
3. 3

   Remove high-voltage service disconnect plug
   Put on high-voltage safety gloves. Unlock the orange service disconnect handle by rotating counterclockwise. Pull the service disconnect plug straight up and out of the receptacle. Inspect the plug and receptacle for any signs of damage, corrosion, or overheating. Store the disconnect plug in a secure location away from the vehicle.
   ⚠️This is the primary high-voltage isolation point. Do not proceed until plug is fully removed and secured.
4. 4

   Verify high-voltage system de-energization
   Wait an additional 5 minutes after removing service disconnect. Using a CAT III 1000V rated multimeter, verify zero voltage across the high-voltage terminals in the service disconnect receptacle. Voltage must read 0V DC. Also verify zero voltage between each terminal and vehicle ground. Document voltage readings.
   ⚠️Do not proceed if any voltage is detected. If voltage is present, reconnect service disconnect and consult manufacturer technical support.
5. 5

   Remove battery pack top cover and protective shields
   Remove the vehicle underbody panels to access the battery pack from below if required. From above, remove all cover screws securing the battery pack upper access cover. Carefully lift and remove the cover to expose the high-voltage connectors, battery modules, and cooling system connections. Remove any protective shields covering the main battery contactors and wiring harnesses.
   Torque spec

   Cover Screws11 Nm (8 lb-ft)
6. 6

   Disconnect battery coolant lines
   Place a coolant drain pan under the battery pack. Locate the battery thermal management coolant inlet and outlet lines. Using appropriate tools, carefully loosen the coolant line fittings. Expect approximately 1-2 quarts of coolant to drain. Plug or cap the open lines to prevent contamination. Inspect fittings and seals for damage.
   ⚠Coolant may be hot if vehicle was recently operated. Wear appropriate PPE to prevent burns.
   Torque spec

   Coolant Line Fittings15 Nm (11 lb-ft)
7. 7

   Disconnect battery module sensors and communication harnesses
   Locate all battery management system sensor connectors on top of the battery pack. Carefully disconnect each connector by releasing the locking tab and pulling straight up. Disconnect the battery pack communication harness connectors. Label each connection for proper reassembly. Remove sensor mounting bolts if sensors must be removed.
   Torque spec

   Sensor Bolts11 Nm (8 lb-ft)

   Connector Bolts7 Nm (5 lb-ft)
8. 8

   Disconnect main high-voltage positive and negative cables
   While wearing high-voltage gloves, locate the main positive and negative high-voltage cable connections at the battery pack terminals. Remove the protective covers. Using insulated tools, remove the high-voltage connector bolts in the proper sequence. Carefully separate the connectors and immediately install protective caps on both cable ends and battery terminals.
   ⚠️Even though system is de-energized, treat all high-voltage components as if they are live. Never allow bare connectors to contact metal surfaces.
   Torque spec

   Connector Bolts7 Nm (5 lb-ft)
9. 9

   Disconnect ground cables and brackets
   Locate all battery pack ground connections to the vehicle chassis. Remove the ground cable bolts using appropriate sockets. Disconnect any remaining mounting brackets or support brackets connected to the battery pack. Store all hardware in labeled containers for reassembly.
   Torque spec

   Ground Cable Bolt14 Nm (10 lb-ft)

   Bracket Bolts20 Nm (15 lb-ft)
10. 10

    Secure and isolate all disconnected components
    Ensure all high-voltage connectors have protective caps installed. Route all disconnected cables away from the battery pack and secure with cable ties to prevent accidental contact. Verify all coolant lines are properly capped. Place warning tags on the service disconnect location and on the steering wheel indicating high-voltage system is disabled. Document the state of all connections with photos if available.
    ⚠Vehicle is not drivable with battery disconnected. Do not attempt to operate vehicle or close high-voltage contactors.

Reassembly

1. Reverse the disassembly procedure, ensuring all high-voltage connectors are clean, dry, and free of damage before reconnection
2. Apply torque to all fasteners in the exact sequence specified in the torque spec list, using a calibrated torque wrench
3. Refill battery coolant system with fresh ACDelco DEX-COOL to proper level and bleed air from system per manufacturer procedure
4. Ensure all sensor connectors are fully seated with locking tabs engaged before reinstalling covers
5. Verify all protective shields and covers are properly reinstalled before reconnecting service disconnect plug
6. Reconnect 12V auxiliary battery (positive first, then negative) and verify vehicle systems initialize properly
7. Use diagnostic scanner to clear any diagnostic trouble codes related to high-voltage system disconnect

Verification

• After reconnecting service disconnect plug, verify green indicator light illuminates indicating proper connection
• Use scan tool to verify battery management system reports all modules communicating with no faults
• Check for coolant leaks around all battery coolant connections after system pressurizes
• Verify battery state of charge matches pre-service reading or has changed only due to expected self-discharge
• Confirm vehicle displays READY status and high-voltage system indicator shows normal operation
• Test vehicle in a safe area to verify normal electric drive operation and regenerative braking function
• Verify no high-voltage system warning lights or messages appear on instrument cluster

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

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