P0513 on 2020-2022 Buick Encore GX: Incorrect Immobilizer Key Causes and Fixes

What's Unique About the 2020-2022 Buick ENCORE GX

The 2020-2022 Buick Encore GX, along with its platform mate the Chevrolet Trailblazer, uses a 'Gen III' Body Control Module (BCM) that is specifically prone to a unique software issue. A low voltage event—such as a battery replacement, jump-start, or the battery dying—can corrupt the BCM's memory. This corruption prevents the BCM from recognizing an otherwise perfectly good key, leading to a P0513 code and a no-start condition. 🎬 Watch: Understanding the P0513 code and how to fix it. GM has issued Technical Service Bulletins (TSBs) that explicitly warn dealers *not* to replace the BCM or perform standard key relearn procedures until a special data reset has been attempted.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Engine will not crank or start.
• Vehicle will not lock or unlock with the key fob (Loss of active functions).
• A "No Key Fob Detected" or "No Remote Detected" message may appear on the driver information center.
• The security indicator light on the dashboard may be flashing or illuminated.
• Check Engine Light is on.
• Engine starts and immediately stalls.

Most Likely Causes

1. Body Control Module (BCM) Memory Corruption After Low Voltage 🔴 High Probability → Shop Body Control Module As documented in TSB #23-NA-165 and #21-NA-277, the Gen III BCM in these vehicles is sensitive to low voltage events (battery change, jump-start), which can cause a software glitch and loss of key memory.
   How to confirm: The problem appeared immediately after a battery replacement, jump-start, or the battery going dead. A GM dealer can confirm the condition by finding P0513 in the ECM and potentially related codes like B389A or B392x in the BCM.
   Typical fix: A dealer must perform a special BCM data reset or reprogramming procedure as outlined in the TSB. This is a software fix, not a hardware replacement. TSB #23-NA-165 calls this a 'GEN3R P0513 DTC Special Data Reset' with a labor time of 0.5 hours. In some cases, the technician may need to open a case with the GM Technical Assistance Center (TAC).
   Est. part cost: $0
2. Weak or Dead Key Fob Battery 🟡 Medium Probability → Shop Vehicle Battery This is a common issue for all vehicles with keyless entry and start. The fob's signal becomes too weak for the car's receiver to detect.
   How to confirm: Try using the vehicle's backup start procedure (placing the fob in the designated pocket in the center console). 🎬 See how to start your Buick with a dead fob battery. If the car starts, the fob battery is the culprit. Alternatively, try the spare key fob.
   Typical fix: Replace the CR2032 battery inside the key fob. 🎬 Watch this easy DIY guide to replacing your key fob battery.
   Est. part cost: $2-$10
3. Faulty Key Fob ⚪ Low Probability → Shop Keyless Entry Transmitter
   How to confirm: A spare key fob works correctly, but the primary one does not, even after a battery change. A locksmith or dealer can test the transponder signal.
   Typical fix: Replace the key fob and have it professionally programmed to the vehicle using a scan tool.
   Est. part cost: $70-$300

Rare But Worth Checking

• Faulty Immobilizer Antenna: → Shop Antenna The antenna ring around the ignition or start button reads the key's signal. If it fails, the signal is never received by the BCM. This is less common than BCM or key fob issues.
• Wiring Issue in the Immobilizer Circuit: A damaged wire or poor connection between the immobilizer antenna and the BCM can prevent the key signal from being validated, causing an intermittent or persistent P0513 code.

Diagnosis Steps

1. Attempt to start the vehicle with your spare key fob. If it works, the issue is with your primary fob.
2. If the spare key doesn't work, replace the battery (typically a CR2032) in the non-working key fob.
3. Try the vehicle's backup starting method. Consult the owner's manual, but this usually involves placing the key fob in a specific pocket located in the center console. If the car starts, it confirms a weak fob battery or signal issue.
4. If the problem started immediately after a battery change or jump-start, do not replace any parts. The vehicle likely needs the software procedure from TSB #23-NA-165 or #21-NA-277.
5. Contact a GM dealership, inform them of the P0513 code and the circumstances (e.g., recent battery change). Reference TSB #23-NA-165 to ensure they perform the correct 'Special Data Reset' instead of attempting unnecessary parts replacement or standard key relearns.
6. If the TSB does not apply or resolve the issue, a technician will need to perform a full diagnostic on the immobilizer system, including the key fob transponder, immobilizer antenna, and BCM circuits.

Parts You'll Likely Need

• Key Fob Battery (OEM #CR2032 (ACDelco P/N: 19333112)) — This is the most common and simplest fix when the key fob's signal becomes too weak.
  Trusted brands: Energizer, Duracell, Panasonic, ACDelco
  OEM price range: $5-$10
  Aftermarket price range: $2-$5
• Keyless Entry Remote Fob (OEM #13532751, 13506668, 13521090 (FCC ID: HYQ4EA)) — Required if the internal transponder chip in the key fob has failed. It must be programmed to the vehicle by a dealer or qualified locksmith.
  Trusted brands: ACDelco
  OEM price range: $150-$300
  Aftermarket price range: $70-$150

Related Codes That Often Appear With This One

• B389A — This BCM code for 'Immobilizer Key Information Incorrect' often accompanies P0513, pointing directly to a security data mismatch within the BCM itself.
• B3924, B3925, B3926, B3927 — These are 'Environment Identification Codes' that can be set in the BCM along with P0513 after a low voltage event, as described in TSB #21-NA-277.

Technical Service Bulletins (TSBs) & Recalls

• 23-NA-165: Vehicle Will Not Lock and Unlock (Loss of Active Functions) Crank or Start (Loss of Passive Functions) with DTC P0513 Set. This TSB explicitly states the cause can be a memory corruption event in the BCM after low voltage and warns not to attempt immobilizer procedures before following the bulletin.
• 21-NA-277: No Crank, No Start, Quick Start/Stall, Key Fobs Inoperative with DTC P0513 and/or B392x codes set. This bulletin provides a detailed diagnostic procedure for the 'Gen III' BCM, warns against module replacement, and describes the need for a special procedure that may require a VCI and contact with the Technical Assistance Center (TAC).

Platform-Specific Known Issues

• TSB #23-NA-165: BCM Memory Corruption After Low Voltage: This TSB documents a known issue where a low voltage condition (e.g., battery replacement, jump-start) can cause BCM memory corruption. This results in a loss of key fob functions (lock/unlock/start) and sets DTC P0513. The official fix is a special dealer-performed software reset called 'GEN3R P0513 DTC Special Data Reset', not module replacement.
• TSB #21-NA-277: Diagnostic Path for No-Start with P0513: This bulletin also addresses a no-start condition with P0513 present after a low voltage event. It provides a specific diagnostic path that warns against replacing modules prematurely and notes that associated BCM codes like B389A and B392x may be present. In some cases, it requires the dealer to open a TAC case to resolve.
• Owner Experience: Sudden No-Start After Battery Service: → Shop Vehicle Battery Owners typically report that the vehicle was working perfectly until the battery was replaced, disconnected for service, or jump-started. After the event, the key fobs completely stop working for both locking/unlocking and starting the vehicle, with a 'No Key Fob Detected' message on the dash. This experience directly aligns with the conditions described in GM's service bulletins.

Scan Tool Commands That Help

• GM SPS (Service Programming System): K9 Body Control Module > Special Data Reset A — This is the initial software reset to be performed when P0513 is set after a low-voltage event, as per TSB #23-NA-165. This attempts to fix the memory corruption without replacing parts.
• GM SPS (Service Programming System): Immobilizer procedure > Body Control Module IMMO Learn with Existing Transponder or Remote Key — This is the second step in the TSB #23-NA-165 procedure, used immediately after the 'Special Data Reset A' to relearn the vehicle's existing key fobs to the now-reset BCM.
• GM SPS (Service Programming System): Immobilizer procedure > Engine Control Module and Body Control Module IMMO Learn — This more involved procedure is required by TSB #23-NA-165 ONLY if a standard immobilizer learn was already attempted before the TSB procedure was followed. This step requires programming two or more NEW key fobs to the vehicle; the old fobs will no longer work.

Wiring & Ground Locations

• K9 Body Control Module (BCM) — Located in the center console, directly behind the lower panel on the passenger side of the vehicle.. The BCM is the central module that experiences the memory corruption leading to P0513. Access is required for diagnosis, part number verification, and potential replacement. GM bulletins warn that disconnecting BCM grounds while the battery is connected can damage the module.

OEM Part Supersession History

• Multiple (GEN3R BCMs) → N/A — The fix for this issue is a software update, not a part replacement. TSB #23-NA-163 lists eligible Base Model Part Numbers (BMPNs) for the GEN3R BCM that can receive this software fix.
  Heads up: BMPNs eligible for this bulletin include: 13518569, 13518570, 13518602, 13518603, 13519619, 13519620, 13519648, 13527252, 13527260, 13527261, 13527297, 13527298, 13527827, 13529492, 13529493, 13533809, 13533813, 13533814, 13533817, 13533821. If the BCM is not one of these GEN3R parts, the TSB does not apply.