Why Is Your TV Switching Off on Its Own?
A TV that turns itself off is one of the most disruptive TV faults — and one of the most common we repair across Nairobi. The good news is that most causes are identifiable and repairable without replacing the TV.
Check the Settings First (Free Fix)
Before assuming a hardware fault, check these settings on your TV:
Sleep Timer
Most TVs have a sleep timer that switches the TV off after a set period (30, 60, 90 minutes etc.). This is often activated accidentally.
- Samsung: Settings → General → System Manager → Time → Sleep Timer
- LG: Settings → General → Timers → Sleep Timer
- Sony: Home → Settings → Device Preferences → Timer → Sleep Timer
- Hisense: Settings → System → Sleep Timer
Auto Power Off / No Signal Off
Many TVs switch off automatically if no signal or no user input is detected for a set period. Disable this in the settings under "Auto Power Off" or "No Signal Auto Off."
If both settings are off and the TV is still switching itself off, you have a hardware fault.
Hardware Causes of a TV That Keeps Switching Off
1. Overheating (Thermal Shutdown)
Every TV has a thermal protection circuit that cuts power if the internal temperature exceeds safe limits. This is why a TV may run fine for 5–10 minutes then suddenly switch off — the components have heated up to the protection threshold.
Causes of overheating:
- TV placed in an enclosed cabinet without airflow
- Ventilation slots covered by dust or obstructions
- Internal cooling fan has failed
- TV placed in direct sunlight
Fix: Ensure the TV has at least 10 cm of clearance on all sides. Vacuum or brush the ventilation slots to remove dust. If the internal fan has failed, it must be replaced (Ksh 2,000–3,500).
2. Failing Capacitors on the Power Supply Board
This is the most common hardware cause of a TV that randomly switches off. Capacitors on the power supply board (the large board inside the TV connected to the mains) age and bulge over time, causing unstable power delivery. As they fail further, the TV may switch off more frequently until it stops turning on at all.
Signs of faulty capacitors: TV takes longer than usual to turn on. Picture flickers before switching off. TV makes a clicking sound before shutting down.
Fix: Capacitor replacement on the power supply board. Cost: Ksh 2,500–4,500. A skilled technician can often replace just the specific capacitors rather than the whole board.
3. Full Power Supply Board Failure
If multiple components on the power supply board have failed, the entire board may need replacement. Cost: Ksh 3,000–7,000 depending on the TV brand and size.
4. Mainboard Issues
The mainboard can also cause unexpected shutdowns if its power management circuit has failed. This is typically diagnosed after the power supply board has been checked.
TV Repair Costs for Switching Off Faults in Nairobi
- Settings adjustment: Free (do it yourself)
- Internal fan replacement: Ksh 2,000 – 3,500
- Capacitor replacement (power board): Ksh 2,500 – 4,500
- Full power supply board replacement: Ksh 3,000 – 7,000
- Mainboard replacement: Ksh 5,000 – 10,000
RepairTech Kenya provides same-day TV repair across all Nairobi estates. We repair Samsung, LG, Sony, Hisense, TCL, Vitron, Skyworth, and all other brands. Call 0742 539 455 or book a repair online.