Diagnosing and Replacing A Defective Capacitor in Your Television Stopping It From Powering ON

TV Capacitor Replacement Introduction

Power Supply Capacitor Has Blown
Some bad capacitors look corroded while others appear to leak glue
One of the most common television problems is a failure to power on, and one of the leading causes of this issue is a defective capacitor. Capacitors play a crucial role in powering electronic devices, including TVs, by storing and releasing electrical energy.

When a capacitor fails, your TV won’t turn on. In this article, we will discuss how to test for a defective TV capacitor and walk through the process of replacing it. If you aren’t completely comfortable with this TV repair, call us @ (888) 488-0975

Step 1: Safety Precautions

Before you begin, it’s essential to prioritize safety:
  1. Disconnect the TV from the power outlet and remove any attached cables.
  2. Let the TV sit for at least 30 minutes to ensure any residual power has dissipated.
  3. Use an anti-static wrist strap to prevent damage to sensitive electronic components.

Step 2: Accessing the Capacitors

  1. Place the TV face down on a soft surface, such as a blanket, to prevent screen damage.
  2. Unscrew and remove the back panel of the TV to expose the internal components.
  3. Locate the power supply board, which is typically near where the power cable connects to the TV.

Step 3: Visual Inspection

Before testing the capacitors, perform a visual inspection:
  1. Check for any bulging, leaking, or ruptured capacitors. A healthy capacitor should have a flat top, but may still be discolored or appear to be leaking glue.
  2. Inspect the solder joints and traces on the board for any signs of damage or cracks in the solder or the board its mounted in.
  3. Take note of any suspect capacitors for further or additional testing.

Step 4: Testing the Capacitors

To properly test a capacitor, you will need a digital multimeter (DMM) with a capacitance measurement function:
  1. Set the DMM to the capacitance setting (typically indicated by a “F” symbol).
  2. Carefully remove the suspect capacitor from the board by desoldering its leads.
  3. Connect the DMM probes to the capacitor’s leads, ensuring correct polarity.
  4. Check the measured capacitance value against the capacitor’s rated value. A significant deviation indicates a faulty capacitor.

Step 5: Replacing the Capacitor

  1. Obtain a replacement capacitor with the same capacitance, voltage rating, and temperature rating as the faulty one.
  2. Insert the leads of the new capacitor through the appropriate holes on the power supply board, ensuring correct polarity.
  3. Solder the leads to the board and trim any excess lead length.
  4. Double-check your work for any solder bridges or cold solder joints.

Step 6: Reassembling and Testing the TV

  1. Carefully reattach the back panel of the TV and secure it with the screws.
  2. Reconnect the power cable and any other cables previously removed.
  3. Power on the TV to verify that the issue has been resolved.

Conclusion

Detecting and replacing a defective capacitor in in your broken TV isn’t difficult if you have some basic repair skills. However, please remember that working on electrical devices can be very dangerous even HOURS after they have been unplugged. Call our TV Repair Technicians if you have any doubts about doing the TV repair yourself. They can be reached at (888) 488-0975