P0562 on 2024 GMC Sierra 3500: System Voltage Low Causes and Fixes

What's Unique About the 2024-2024 Gmc SIERRA 3500

For the 2024 GMC Sierra 3500 and its platform-mate, the Chevrolet Silverado HD, P0562 is not just a simple low voltage code. 🎬 Watch: P0562 causes, symptoms, and how to fix it. It is frequently accompanied by DTC P0606 (Control Module Processor Performance) and is the subject of GM Technical Service Bulletin #24-NA-050. The bulletin, originally released in March 2024, explains that a temporary low voltage event, such as from a weak battery during engine cranking, a jump start, or even during battery charging, can cause a diagnostic anomaly in the Electronic Brake Control Module (EBCM). This sensitivity incorrectly sets the P0606 fault, which in turn illuminates the Check Engine Light. A June 2024 revision to the TSB updated the primary fix to reprogramming the EBCM, indicating the issue is a software calibration problem.

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 (Malfunction Indicator Lamp) is on.
• Battery or charging system warning light illuminated.
• Difficulty starting the engine or a no-start condition.
• Dimming or flickering headlights and interior lights.
• Erratic operation of electrical components.
• Engine may stall intermittently, especially when shifting into gear after a jump start.
• "Service Brake System" or "Service StabiliTrak" messages on the Driver Information Center (DIC).

Most Likely Causes

1. Low Battery State of Charge Triggering EBCM Fault (per TSB #24-NA-050) 🔴 High Probability → Shop Vehicle Battery The EBCM software calibration on this model is sensitive to temporary voltage drops during cranking, jump starts, or battery charging, causing it to set a P0606 fault alongside the P0562. GM has identified this as a software diagnostic anomaly.
   How to confirm: Check for both P0562 and P0606 codes stored in history. Perform a battery health test (load test) using a tool like the GM GR8 tester to check for a weak or failing battery. A healthy battery should read approx. 12.6V engine-off and 13.5-14.7V engine-on.
   Typical fix: Do NOT replace the EBCM. The official fix, per a June 2024 revision of TSB #24-NA-050, is to reprogram the Electronic Brake Control Module (EBCM) with updated software. If the battery fails a load test, it should also be replaced. A professional scan tool is required to clear the DTCs from the EBCM. The warranty labor operation for the original test and reset was 0.4 hours.
   Est. part cost: $210-$370 for a new AGM battery.
2. Failing Battery 🟡 Medium Probability → Shop Vehicle Battery Modern heavy-duty trucks have a high electrical demand, which strains the battery. The original AGM battery has a typical service life of 3-5 years and may be reaching its end.
   How to confirm: Measure battery voltage with the engine off using a multimeter. A healthy battery should read approximately 12.6 volts. Perform a load test, as a battery can show good voltage but fail under load. For 2024 HD trucks, the OE battery is an AGM type with 730 CCA.
   Typical fix: Replace the battery. The 2024 Sierra 3500 typically uses an AGM battery of H6 (94R) group size. 🎬 Watch: Step-by-step battery replacement for 2019-2024 Silverado and Sierra trucks. After replacement, a battery relearn procedure may be needed using a scan tool to reset the Battery Sensor Module.
   Est. part cost: $210-$370.
3. Failing Alternator 🟡 Medium Probability → Shop Alternator
   How to confirm: With the engine running, measure the voltage at the battery terminals. It should be between 13.5 and 14.7 volts. If the voltage is low (below 13.2V) or not increasing with the engine on, the alternator is likely faulty. 🎬 See this easy way to diagnose a failing GM alternator. You can also perform a load test by turning on all accessories.
   Typical fix: Replace the alternator. Depending on the engine (gas/diesel) and options (single/dual), the amperage will vary.
   Est. part cost: $658-$926 for the part.
4. Loose or Corroded Battery Terminals/Cables ⚪ Low Probability → Shop Vehicle Battery
   How to confirm: Visually inspect the battery terminals for corrosion (white or greenish powder). Check that the cable clamps are tight and cannot be moved by hand. Check the main power and ground cables for tightness and integrity.
   Typical fix: Clean the battery terminals and cable ends with a wire brush and a cleaning solution. Tighten all connections securely and apply dielectric grease to prevent future corrosion.
   Est. part cost: $5-$20 for cleaning tools.

Rare But Worth Checking

• Poor Ground Connection: A corroded or loose main ground strap from the engine/chassis to the battery can cause widespread electrical issues, including low voltage readings at the PCM. A Reddit user with a similar late-model Sierra suspected a BCM ground for intermittent electrical issues including a P0562.
• Parasitic Battery Drain: → Shop Vehicle Battery An electrical component that does not shut off when the vehicle is turned off can drain the battery overnight, leading to a low voltage state on startup. Diagnosing this requires a key-off draw test, isolating circuits by pulling fuses to find the source of the drain. GM has a related diagnostic procedure under document 24-NA-229 for this condition on many 2020-2025 vehicles.

Diagnosis Steps

1. Check for other diagnostic trouble codes. The presence of P0606 is a key indicator to follow TSB #24-NA-050.
2. Inspect the battery terminals and cables for corrosion and ensure they are tight.
3. With the engine off, use a multimeter to test the battery voltage. A reading below 12.4V indicates a discharged or failing battery.
4. Perform a battery load test using a professional tester (e.g., GM GR8). This is the most reliable way to determine battery health.
5. Start the engine and measure the voltage at the battery terminals. The reading should be between 13.5V and 14.7V. If it's low, the alternator is suspect. If it's high, the voltage regulator (internal to the alternator) may be at fault.
6. If the battery and alternator test good, inspect the main engine and chassis ground connections for corrosion or looseness. Key locations on GM trucks often include the battery-to-chassis strap, cylinder heads, and firewall.
7. If P0606 is present, follow the revised TSB guidance: Reprogram the EBCM with the latest software via a GM dealer or qualified shop. Do NOT replace the EBCM.
8. Use a professional scan tool (GDS2) to clear the codes from the EBCM after reprogramming, as simply disconnecting the battery may not work.

Parts You'll Likely Need

• AGM Battery (OEM #ACDelco Gold 88865934 (Group 94R/H7)) — A weak or failing battery is the most common trigger for P0562, especially in the context of TSB #24-NA-050. The 2024 HD trucks use a 730 CCA AGM battery from the factory.
  Trusted brands: ACDelco, DieHard, Duralast
  OEM price range: $250-$400
  Aftermarket price range: $210-$370.
• Alternator (OEM #85063114 (170 Amp, Gas Engine, may vary)) — If the battery is healthy but not being charged correctly, the alternator is the next most likely cause.
  Trusted brands: ACDelco GM Original Equipment, Bosch, Duralast Gold
  OEM price range: $212-$400 (Part cost varies significantly by amperage and supplier).
  Aftermarket price range: $350-$700.

Related Codes That Often Appear With This One

• P0606 — As described in TSB #24-NA-050, a low voltage condition (P0562) can cause the Electronic Brake Control Module (EBCM) to log a P0606 processor fault. They are directly linked on this vehicle.
• P0563 — This code for 'System Voltage High' is also mentioned in TSB #24-NA-050. It indicates the opposite problem but is related to the same EBCM sensitivity to voltage fluctuations, often during battery charging or jump-starting.

Technical Service Bulletins (TSBs) & Recalls

• 24-NA-050: "Silverado and Sierra Setting DTC P0606 and either DTC P0562 or P0563" - This bulletin is the primary source for understanding this specific code combination on this truck. It advises against EBCM replacement and points to battery state of charge as the likely trigger, noting a software update is in development.

Platform-Specific Known Issues

• TSB #24-NA-050 documents an issue where a low or high voltage state can cause the Electronic Brake Control Module (EBCM) to set DTC P0606, which in turn illuminates the Check Engine Light. The primary fix is to address the voltage condition (e.g., replace a weak battery) and clear the codes, not replace the EBCM.

Mechanic-Grade Diagnostic Values

• System Voltage (Engine Off) — expected: ~12.6 Volts. Failure: A reading below 12.4V indicates a discharged or potentially failing battery.
• Charging System Voltage (Engine Running at Idle) — expected: 13.5 - 14.7 Volts. Failure: Voltage below 13.2V suggests a faulty alternator or wiring issue. Voltage above 15.0V suggests a faulty voltage regulator.
• P0562 Trigger Condition — expected: Voltage must remain above ~10 Volts.. Failure: System voltage drops below 10 volts for a sustained period (e.g., 60 seconds), triggering the code.

Scan Tool Commands That Help

• GDS2 (GM Global Diagnostic System 2): Module Diagnostics > EBCM > Clear DTCs — Required to clear the P0606 code from the Electronic Brake Control Module. Simply disconnecting the battery may not clear the fault, per TSB #24-NA-050.
• GDS2 / SPS2 (Service Programming System 2): Service Programming > Reprogram ECU > EBCM — This is the official updated repair procedure per the June 2024 revision of TSB #24-NA-050 to correct the software anomaly that causes P0606 to set during a low voltage event.
• GDS2 (GM Global Diagnostic System 2): Data Display > BCM — To monitor the status of various inputs and outputs of the Body Control Module to check for anomalies that could indicate a parasitic draw, such as sensors that are not going to sleep.

Wiring & Ground Locations

• Main Chassis Ground — Typically a strap from the negative battery terminal to the vehicle's frame or engine block.. A poor main ground connection is a common cause of low system voltage and widespread electrical problems. This is a primary inspection point for any P0562 code.
• EBCM Ground — The ground wire for the Electronic Brake Control Module, typically grounded to the chassis near the module itself.. A specific ground issue for the EBCM could cause it to malfunction or misread system voltage, potentially contributing to the P0606 fault, although the TSB points to a software issue.
• Common Body Grounds (e.g., G101, G104) — Located on cylinder heads, firewalls, and behind A-pillar kick panels on many GM trucks.. Multiple vehicle systems share these grounds. A loose or corroded connection can cause intermittent and hard-to-diagnose electrical faults that could lead to a low voltage condition or erratic module behavior.

Real Owner Repair Stories

• r/gmcsierra Reddit user comment (2024 Chevrolet Silverado (platform mate)) — Persistent dead battery condition, requiring multiple trips to the dealer.
  ❌ Tried (didn't work) Replacing the battery (diagnosed with a 'bad cell')., Replacing a 'bladder control module' in the passenger seat., Replacing the 'driver monitoring assist module'.
  ✅ What actually fixed it The issue was ultimately traced to a faulty Body Control Module (BCM). A GM engineer was reportedly needed to diagnose it, indicating it was a non-obvious parasitic drain.

When the Usual Fixes Don't Work

• While TSB #24-NA-050 points directly to an EBCM software issue triggered by low voltage, real-world owner reports indicate that a persistent low voltage state (and thus P0562) can be caused by other underlying issues. In one documented case, a faulty Body Control Module (BCM) was causing a parasitic drain that repeatedly killed the battery. The dealer's initial attempts to fix the issue by replacing the battery and other modules failed, and the root cause was only found after deeper diagnosis. This highlights that while the EBCM software update is the correct fix for the P0606 *symptom*, technicians must still diagnose the root cause of the P0562 *trigger*, which may not always be a simple battery failure.

Model Year Variations Within This Range

• 2024: The official GM repair procedure for the P0562/P0606 combination was changed in June 2024 via a revision to TSB #24-NA-050. The fix was updated from 'Test Battery and Reset' to 'Reprogram the EBCM'. Vehicles serviced after this date should receive the software update.