B3055 on 2020-2025 Cadillac XT6: 'Key Not Detected' and No-Start Causes

What's Unique About the 2020-2025 Cadillac XT6

The Cadillac XT6 and its platform mates (Chevy Traverse, Buick Enclave) use a sophisticated keyless push-to-start system that is sensitive to radio frequency interference (RFI). General Motors has issued multiple versions of Technical Service Bulletin #PIC5650, which specifically call out B3055 in relation to intermittent no-start conditions caused by RFI from aftermarket devices like phone chargers, dash cams, or even some LED interior lights. Before suspecting a failed part, the diagnostic process for an XT6 must begin with ruling out these external interference sources, which are a very common cause of this code on modern GM platforms.

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.
• Engine starts and immediately stalls.
• "No Remote Detected" or "Key Not Detected" message on the Driver Information Center (DIC).
🎬 Watch: How to start your XT6 when no remote is detected
• Security indicator light (icon of a car with a lock) is illuminated or flashing.
• Remote key fob functions (lock/unlock) may work, but the vehicle still won't start.
• Vehicle may start only when the key fob is placed in the designated transmitter pocket.

Most Likely Causes

1. Weak or Dead Key Fob Battery 🔴 High Probability → Shop Vehicle Battery Key fobs for keyless start systems transmit constantly and their batteries (typically CR2032) have a finite life of 1-3 years.
   How to confirm: Try starting the vehicle by placing the key fob in the dedicated transmitter pocket. For the XT6, this is a depression at the bottom of the center console storage area. 🎬 See exactly where to find the transmitter pocket in your Cadillac If the vehicle starts, the fob battery is almost certainly weak. Alternatively, try the spare key fob.
   Typical fix: Replace the CR2032 battery inside the key fob. 🎬 Follow this quick walkthrough to replace your key fob battery
   Est. part cost: $2-$10
2. Radio Frequency Interference (RFI) 🔴 High Probability As noted in multiple versions of GM TSB PIC5650, the keyless entry system on modern GM vehicles is highly sensitive to RFI from aftermarket devices plugged into the 12V outlets (e.g., phone chargers, dash cams, FM transmitters, wireless phone charging pads). The TSB even notes that aftermarket LED interior lights can cause enough interference to block the key fob signal.
   How to confirm: Unplug all aftermarket electronic devices from the vehicle's power outlets. Remove other keys, fobs, and RFID cards from the keychain. Attempt to start the vehicle again. If it starts, one of the removed devices was the cause.
   Typical fix: Remove the interfering device or replace it with a higher-quality, better-shielded alternative. Avoid cheap, unbranded chargers.
   Est. part cost: $0
3. Faulty Key Fob 🟡 Medium Probability → Shop Keyless Entry Transmitter Key fobs can be damaged by being dropped or exposed to moisture, causing the internal transponder chip to fail.
   How to confirm: Attempt to start the vehicle with all available spare keys. If another key works reliably, the original key fob is faulty. Even with a new battery, a faulty fob will not start the car outside of the transmitter pocket.
   Typical fix: The faulty key fob must be replaced and programmed to the vehicle by a dealer or qualified automotive locksmith. The OEM part number is often 13544052 or 13522879.
   Est. part cost: $150-$400
4. Faulty Remote Control Door Lock Receiver (RCDLR) or Antenna ⚪ Low Probability → Shop Keyless Entry Receiver The RCDLR module is responsible for receiving signals from both the key fobs and the Tire Pressure Monitoring System (TPMS) sensors. A failure in this module or its antenna can disrupt both systems.
   How to confirm: This is often diagnosed when B3055 appears alongside TPMS codes (like C0750, C0755, etc.), as mentioned in TSB PIC5650M. This requires professional diagnosis with a scan tool to check module communication. A similar issue on the Cadillac XT5 is noted in TSB 16-NA-396.
   Typical fix: Replace the faulty RCDLR module or antenna and program the new module to the vehicle.
   Est. part cost: $200-$500

Rare But Worth Checking

• Body Control Module (BCM) Issue: → Shop Body Control Module A BCM failure is rare but possible, as mentioned in TSB #PIC5650M. It should only be considered after all other causes, especially RFI and key fob issues, have been exhaustively ruled out. A failing BCM often causes other unrelated electrical problems.

Diagnosis Steps

1. Check the Driver Information Center (DIC) for messages like 'No Remote Detected'.
2. Unplug ALL aftermarket devices (phone chargers, dash cams, etc.) from the 12V power outlets. Pay special attention to any wireless phone chargers or USB hubs.
3. Remove any other key fobs, access cards, or RFID-blocking wallets from the immediate vicinity of the driver's seat.
4. Attempt to start the vehicle. If it starts, the issue is RFI. Re-introduce items one by one to find the culprit.
5. If it doesn't start, try the spare key fob. If the spare works, the primary fob is faulty.
6. If the spare fob also fails, place the primary fob in the transmitter pocket. In the XT6, this is a fob-shaped depression at the bottom of the center console storage area. Try to start the engine. If it starts, the fob battery is the most likely culprit.
7. Replace the CR2032 battery in the key fob.
8. Check the main 12V vehicle battery to ensure it is fully charged and in good health, as low voltage can cause unpredictable electronic issues, even if it doesn't directly cause B3055.
9. If the vehicle still won't start, use a professional-grade scan tool to check for other codes, especially BCM, RCDLR, and TPMS codes.
10. If other codes are present, follow the diagnostic procedures for those codes, which may point to a module or wiring issue requiring professional service.

Parts You'll Likely Need

• Key Fob Battery — This is the most common and inexpensive cause for a weak signal from the key fob, leading to the B3055 code.
  Trusted brands: Energizer, Duracell, Panasonic
  OEM price range: $5-$10
  Aftermarket price range: $2-$8
• Keyless Entry Remote Fob (OEM #13544052 (interchangeable with 13522879, 13547851)) — If the fob's internal transponder is damaged, the entire fob must be replaced and programmed to the vehicle.
  Trusted brands: ACDelco
  OEM price range: $150-$300
  Aftermarket price range: $70-$150
• Remote Control Door Lock Receiver (RCDLR) — In rarer cases, the module that receives the key's signal fails. This is often suspected when TPMS codes are also present.
  Trusted brands: ACDelco
  OEM price range: $200-$400
  Aftermarket price range: $150-$300

Related Codes That Often Appear With This One

• B3060 — This code also relates to key transponder issues and often appears with B3055 during a key recognition failure.
• B3935 — Indicates a transponder authentication failure, which is part of the same security handshake process that fails and logs B3055.
• C0750, C0755, C0760, C0765, C0775 — These are TPMS codes. The same module (RCDLR) receives signals for both the key fob and tire pressure sensors. Their simultaneous appearance with B3055 strongly suggests either a faulty RCDLR or significant radio frequency interference.

Technical Service Bulletins (TSBs) & Recalls

• PIC5650M: Addresses intermittent no crank, no start, or start stall with the security light on, listing B3055 as a potential code and advising to check for RFI from a long list of aftermarket devices before replacing parts.
• TSB 16-NA-396: While for the XT5, it notes similar 'No Fob Detected' issues can be caused by an internal fault in the RCDLR module, which is relevant context.

Platform-Specific Known Issues

• Per TSB #PIC5650M, this vehicle is susceptible to intermittent no-crank or start-stall conditions that log code B3055, often due to radio frequency interference from aftermarket accessories.
• The transmitter pocket for emergency starts is located inside the center console storage area, at the bottom. You may need to lift a storage tray to access it.

Mechanic-Grade Diagnostic Values

• Main 12V Vehicle Battery Voltage — expected: 12.4V or higher (Key On, Engine Off). Failure: Voltage below 11.5V can cause erratic behavior in the BCM and other modules, potentially leading to key authentication failures and a B3055 code.

Hidden / Shadow Codes Worth Checking

• B3055 00: The '00' is a symptom byte meaning 'No Sub Type Information'. This indicates that the base DTC B3055 provides the complete description of the failure and no further detail is available. It confirms the issue is a general failure to detect the transponder. (see via GM GDS2/Techline Connect or other advanced, dealer-level scan tools.)

Scan Tool Commands That Help

• GM GDS2: Immobilizer Data List — This is a primary diagnostic step. Use this to view live data parameters like 'Transponder Key Status' and 'Environment Identification'. A status of 'No Key Detected' confirms the BCM is not receiving a signal, pointing the diagnosis toward the key fob, antennas, or RFI.
• GM GDS2 / SPS2: Immobilizer Learn / Programming Theft Deterrent System Components — This function is required after replacing a key fob or the Body Control Module (BCM). It pairs the new component to the vehicle's security system. An attempt to start the engine with an unlearned component will result in a B3055 or related code.

Wiring & Ground Locations

• Keyless Entry (PEPS) Antennas — The XT6 uses multiple small antennas. They are strategically placed in locations such as the front and rear bumpers, inside the center console, and potentially in the door panels or liftgate.. While a faulty antenna more commonly sets codes like B3925, severe RFI near an antenna or a complete failure of the center console antenna (used for starting) can contribute to a B3055 'no transponder' condition.
• Transmitter Pocket (Emergency Start Slot) — Inside the center console storage area. You may need to lift a removable tray to see the fob-shaped depression at the bottom.. This pocket contains a dedicated antenna that communicates directly with the key fob, bypassing the normal passive entry antennas. If the vehicle starts when the fob is in this pocket, it strongly indicates the issue is a weak fob battery or a problem with the other PEPS antennas, not a faulty fob transponder.

Real Owner Repair Stories

• Go-Parts.com / YouTube - ADD AUTOMOBILE SERVICES (2013 Chevrolet Equinox (uses similar GM immobilizer logic to the XT6)) — Intermittent no-start with security light on and code B3055.
  ❌ Tried (didn't work) Initial diagnosis was inconclusive before being taken to a workshop.
  ✅ What actually fixed it A workshop identified a defective plug connection at the Body Control Module (BCM). The fix was to clean the connector pins and apply dielectric grease, which restored full functionality and resolved the code without replacing the BCM.

OEM Part Supersession History

• 13522879 → 13544052, 13547851, 13522880, 13544054 — Standard part number updates and revisions by the manufacturer.
  Heads up: These part numbers are generally interchangeable for the specified vehicle range. Always verify compatibility with the vehicle's VIN before purchasing. The key operates at 433 Mhz and has an FCC ID of HYQ2ES.

Model Year Variations Within This Range

• 2020-2025: No significant variations in the keyless entry system, causes of B3055, or diagnostic procedures have been documented within this model year range for the Cadillac XT6. The system is consistent across this generation.