P0607 on 2020-2022 Cadillac CT5: BCM Performance Fault Causes and Fixes

What's Unique About the 2020-2022 Cadillac CT5

On most vehicles, a P0607 code points to a critical failure in the main Powertrain Control Module (PCM). However, on GM's Global B electrical architecture used in the CT5 and its platform mates, this code is specifically assigned to a known software anomaly within the Body Control Module (BCM). GM has issued multiple Technical Service Bulletins (TSBs) acknowledging this, stating the BCM is setting the code and illuminating the Check Engine Light. This distinction is critical, as it redirects diagnosis away from the engine computer and towards the BCM.

Diagnostic Flowchart

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

Symptoms You May Notice

• Check Engine Light (MIL) illuminated on the Driver Information Center (DIC).
• Remote start may be inoperative while the Check Engine Light is active.

Most Likely Causes

1. Internal BCM Software Anomaly 🔴 High Probability This is a known issue acknowledged by GM in Technical Service Bulletin #22-NA-044. It affects multiple vehicles on the Global B platform.
   How to confirm: A technician would confirm the code is stored in the BCM using a GM-compatible scan tool and check for applicable service bulletins.
   Typical fix: Per TSB #22-NA-044, the initial fix is to reset the BCM by removing the vbatt 1 (F49DR BCM1) and vbatt 2 (F4DR BCM 2) fuses for five minutes, then reinstalling and clearing all DTCs. This is not the same as a simple battery disconnect. If the issue persists, a BCM software update by a dealer is required. The TSB explicitly states 'Do not replace the BCM' as the first step.
   Est. part cost: $0
2. Low Battery Voltage or Power Supply Issue 🟡 Medium Probability → Shop Vehicle Battery Modern vehicles with complex electrical systems are sensitive to voltage fluctuations. A weak battery can cause various modules, including the BCM, to behave erratically and log performance codes. One owner reported a faulty OnStar module was the root cause of a draining battery, which triggered the check engine light.
   How to confirm: Test the battery, starting, and charging systems. Ensure battery voltage is stable and within the 12.2V - 12.7V range with the engine off. A professional load test is recommended.
   Typical fix: Recharge or replace the battery. Clean or tighten battery terminals and ground connections. Address any parasitic drains, such as the faulty OnStar module mentioned by an owner.
   Est. part cost: $150-$350

Rare But Worth Checking

• Faulty Body Control Module (BCM): → Shop Body Control Module While the TSB explicitly states NOT to replace the BCM for the known software glitch, a genuine hardware failure of the module is still possible, though less likely. This should only be considered after all software and reset procedures have been exhausted.
• BCM Power or Ground Circuit Issue: A poor connection, corroded wire, or damaged harness supplying power or ground to the BCM can cause it to malfunction and set a performance code. This would require manual circuit tracing and testing.

Diagnosis Steps

1. Connect a professional OBD-II scanner capable of reading codes from all modules, not just the ECM.
2. Verify that DTC P0607 is stored in the Body Control Module (BCM).
3. Check for any applicable Technical Service Bulletins (TSBs) for P0607 on this vehicle. Specifically, reference TSB #22-NA-044.
4. Test the vehicle's battery and charging system to rule out any voltage-related issues.
5. Following the procedure in TSB #22-NA-044, perform a BCM reset by removing the vbatt 1 (F49DR BCM1) and vbatt 2 (F4DR BCM 2) fuses for five minutes.
6. Reinstall the fuses and use a scan tool to clear all DTCs.
7. Allow all modules to power down, then start the vehicle to see if the Check Engine Light returns.
8. If the light returns, the BCM requires reprogramming with the latest software by a GM dealership. This is a warranty-covered repair.
9. Only after all software and reset procedures have failed 🎬 See this walkthrough on how to replace a BCM should BCM replacement be considered.

Parts You'll Likely Need

• Body Control Module (BCM) (OEM #84922494 (superceded by 13546978), 13541807 (CT4 example)) — This is the module that sets the code. While TSBs advise against replacement as a first step, a hardware failure would require a new BCM, which must be programmed by the dealer. 🎬 Watch: How to perform a GM BCM setup and relearn Part numbers can vary by model year and options.
  Trusted brands: ACDelco, GM Genuine Parts
  OEM price range: $400-$600

Technical Service Bulletins (TSBs) & Recalls

• Bulletin #22-NA-044: States that a BCM software anomaly can set P0607 and advises performing a specific fuse-pull reset instead of replacing the BCM. It also lists numerous other GM vehicles affected by the same issue. The labor operation code for this warranty work is 2888468.
• Bulletin #PIE0672B: An earlier engineering information request to gather data on vehicles with P0607 set in the BCM to determine the root cause, confirming GM's long-term investigation into this specific issue.

Platform-Specific Known Issues

• GM has issued Technical Service Bulletin #22-NA-044 for the 2020-2022 Cadillac CT5 (and other models) which states that an internal BCM software anomaly can cause DTC P0607 to be set. The bulletin explicitly advises against replacing the BCM as the initial step.
• The specific fix outlined in TSB #22-NA-044 is to perform a targeted BCM reset by pulling specific fuses for five minutes, not a general battery disconnect.

Mechanic-Grade Diagnostic Values

• BCM Power Supply Voltage — expected: 12.2 V ± 0.5 V. Failure: Voltage below 12.0V or unstable readings can cause module performance codes.
• BCM Ground Circuit Resistance — expected: Below 0.1 Ω. Failure: Higher resistance indicates a poor ground connection, which can lead to erratic module behavior.
• Alternator Output Voltage (at battery) — expected: 13.5V - 14.5V with engine running. Failure: Voltage outside this range indicates a charging system problem that can affect all modules.

Scan Tool Commands That Help

• GDS2 (Global Diagnostic System 2): Vehicle DTC Information — To scan all vehicle modules and confirm that the P0607 code is specifically stored in the Body Control Module (BCM), which is critical for this vehicle-specific diagnosis.
• GM SPS (Service Programming System) via Techline Connect: Replace and Program ECU / BCM Setup — This function is required if the TSB fuse-pull reset fails and the BCM needs a software update, or if the BCM is replaced. It downloads the correct calibration and RPO configuration from GM's servers and flashes it to the module.
• GDS2: Clear All DTCs — Used after performing the fuse-pull reset procedure outlined in TSB #22-NA-044 to ensure all modules start from a clean slate before re-evaluating if the fault returns.

Wiring & Ground Locations

• Body Control Module (BCM) — Inside the passenger cabin, located under the dashboard on the driver's side, to the far left, behind the lower kick panel. It is often mounted with plastic clips.. This is the physical location of the module setting the code. Access is required to check its connectors for integrity, perform the fuse-pull reset (fuses are in the interior fuse block), or replace the unit.
• Connector X210 — Mounted at the base of the left A-pillar, accessible after removing the driver's front side door sill garnish molding (kick panel).. While not directly cited for P0607, other GM TSBs identify this as a critical data communication connector. A bent or corroded terminal in this connector can cause widespread communication issues between modules, potentially leading to performance codes.
• BCM Ground Path — General location is a ring terminal, splice pack, or inline harness connector connected to the chassis, often near the BCM itself.. A GM service bulletin warns that removing a BCM ground path while the battery is connected can cause internal damage to the module. This is a critical warning for any technician manually testing ground circuits.

Real Owner Repair Stories

• CorvetteForum Discussion (2024 Chevrolet C8 Corvette (Global B Platform Mate)) — Dealer service action to reprogram the BCM for DTC U1962 (a related communication code).
  ✅ What actually fixed it The dealer performed a preventative BCM software update (reprogramming) as part of a service campaign. The owner reported no issues after the update. This corroborates that BCM reprogramming is a common fix for module-related codes on this platform.

OEM Part Supersession History

• Multiple older part numbers → 84922494 — Standard part evolution and consolidation for various GM models.
  Heads up: The part number 84922494 is listed for a wide range of GM vehicles over many years, but it is NOT the correct part for a 2020-2022 Cadillac CT5. The CT5 uses a newer generation BCM specific to the Global B platform. The part number from Pass 2, 13546978, is a more plausible candidate, but must be verified by VIN. Installing an incorrect BCM, even if it physically connects, will not work.

Model Year Variations Within This Range

• 2020+: Vehicles on the Global B electrical architecture, like the CT5, require the ignition to be OFF during module programming via the Ethernet-enabled DLC pins. This is a significant departure from older GM vehicles where the ignition is typically ON.