Samsung Galaxy S24 Ultra Error SEC_BATT_ERR_04: Fast Charging Low Temperature Alert
SEC_BATT_ERR_04 indicates a battery thermal monitoring fault where the Power Management IC (PMIC) detects an out-of-spec low-temperature reading (typically below -5°C/23°F) from the thermistor line. Charging is suspended to prevent lithium plating and permanent dendritic damage to the pouch cell.
Hardware Diagnostic Matrix
Spec Ref #784b4ae2Required Diagnostic Tools & Instrumentation
Multimeter Probing Targets & Circuit Tolerances
Bench Calibrated ±5%| Test Point / Circuit | Target Nominal Spec | Expected State | Fault Condition |
|---|---|---|---|
| Main Logic DC Bus | 3.3V / 5.0V DC (±0.1V) | Stable DC Potential | <2.9V (Brownout / Sag) |
| Thermistor / NTC Sensor | 10kΩ - 100kΩ @ 25°C | Smooth Thermal Curve | 0Ω (Short) or ∞ (Open) |
| Safety Ground / PE Continuity | < 0.5Ω Resistance | Solid Earth Bond | > 1.0Ω (Floating Chassis) |
Common Symptoms & Fault Manifestations
- Battery icon displays a yellow triangle with a thermometer icon
- Pop-up notification stating 'Charging paused: Battery temperature too low'
- Fast charging and Super Fast Charging 2.0 (45W) fail to initiate via USB-PD
Root Causes & System Failure Modes
Fractured solder joints or failed 47kΩ/100kΩ NTC thermistor on the wireless charging coil flex or sub-PBA
Sub-PBA to mainboard interconnect FPC flex cable unseated, oxidized, or torn along the TH_BATT sense line
Liquid ingress or corrosion bridging pull-up/pull-down resistor arrays in the PMIC thermal sensing circuit
High-Voltage & Mechanical Safety Isolation
Prior to opening access panels, disconnecting terminals, or probing wiring, perform complete lock-out / tag-out (LOTO). Disconnect all AC mains, DC string isolators, and lithium battery banks. Allow internal smoothing capacitors at least 3 to 5 minutes to dissipate stored residual energy below safe threshold (<30VDC).
Step-by-Step Diagnostic & Resolution Procedure
Safe Isolation & Device Opening
Power down the device completely. Heat the rear glass assembly uniformly to 75°C for 5 minutes using a heating plate or mat. Use a suction cup and thin pry picks to slice the perimeter adhesive. Carefully release the back glass, avoiding internal flex ribbons.
Physical & Multimeter Inspection
Inspect the wireless charging coil assembly, which houses the primary ambient/charging NTC thermistor. Using a multimeter set to resistance (ohms), measure the thermistor terminals at 25°C room temperature; expected nominal value is 47kΩ or 100kΩ (depending on revision). If reading Open Loop (OL) or short (<1kΩ), the thermistor is damaged.
Component Repair or Replacement
Clean the main FPC interconnect terminals and sub-board connectors with 99.9% IPA to eliminate micro-corrosion causing high-resistance false pull-downs. If the thermistor line remains open, replace the wireless charging NFC/thermal flex assembly and verify the sub-board interconnect cable is fully latched.
Recalibration & Verification
Reattach the battery connector and power on the phone. Dial *#0228# in the Samsung Phone dialer to enter BatteryStatus Mode. Confirm the thermistor readout reports actual ambient temperature (~22-26°C) and voltage is stable. Plug in a 45W PPS charger to verify Super Fast Charging 2.0 activates normally.
Hardware Reset & Fault Clear Sequence
Controller ProcedurePrevention & Routine Maintenance Guidelines
- Prevent condensation exposure by avoiding sudden shifts from freezing outdoor environments to high humidity rooms.
- Ensure OEM-grade replacement parts are used, as non-OEM wireless coils frequently omit or use out-of-spec thermistors.
Frequently Asked Diagnostic Questions
What does error code SEC_BATT_ERR_04 indicate on Samsung Galaxy S24 Ultra?
SEC_BATT_ERR_04 indicates a battery thermal monitoring fault where the Power Management IC (PMIC) detects an out-of-spec low-temperature reading (typically below -5°C/23°F) from the thermistor line. Charging is suspended to prevent lithium plating and permanent dendritic damage to the pouch cell. In engineering telemetry, it indicates fast charging low temperature alert requiring circuit verification.
What are the primary triggers causing error SEC_BATT_ERR_04?
Diagnostic bench telemetry isolates the following common root causes: Fractured solder joints or failed 47kΩ/100kΩ NTC thermistor on the wireless charging coil flex or sub-PBA; Sub-PBA to mainboard interconnect FPC flex cable unseated, oxidized, or torn along the TH_BATT sense line; Liquid ingress or corrosion bridging pull-up/pull-down resistor arrays in the PMIC thermal sensing circuit.
How do I reset and clear Samsung error SEC_BATT_ERR_04?
Disconnect the main battery flex for 60 seconds to discharge the PMIC capacitors. Reconnect, boot to recovery (Power + Volume Up while connected to a PC), select 'Wipe Cache Partition', and reboot to clear latch-up thermal state flags. If the error status repeats immediately after clearing, discontinue clearing and test circuit continuity.
Can I safely resolve error SEC_BATT_ERR_04 without specialized shop tooling?
This fault is graded as Intermediate difficulty with High severity. Standard diagnostics require an insulated digital multimeter and appropriate hand tools. Always observe high-voltage isolation procedures.