I have a bust LCD TV - I've already ordered a replacement but am interested in using the broken TV to learn a little more about how these are put together and if I'm lucky fix it to have as a spare. Most of the information I've found for the TV's symptoms (standby light on, but won't power up) points to the capacitors so that's what I've been focusing on.
I've have looked across all of the immediately visible capacitors and none are showing bulging / leaking electrolyte, so I pulled out the power board and have now removed two capacitors to test.
It turned out my trusty old automotive multimeter didn't have a capacitance setting so I went to the local electrics shop and bought a relatively cheap auto-ranging multimeter which they recommended as being quite popular. I'm not use to autoranging meters so this new toy is taking me a little while to get used to anyway.
When testing the capacitors which I have removed I get a range of different values. The multimeter is quite slow to respond (I believe this is from the meter charging the capacitor before making the reading?) and will switch it's range which has confused me a few times.
My method of testing is to have the meter on capacitance setting. It will usually show a reading of 0.04nF with the leads not touching anything. Once touching the probes to the capacitor (taking care with polarity), I get my results after 2-3 seconds.
The capacitors I'm testing are a 35v 1000uF and 35v 450uF. The readings I'm getting will be have ranged around ~1.4nF, once or twice around ~30nF and a few times OL.
I don't know how to interpret this.
I'm not sure if this is: 1) Indicative of bad capacitors 2) Cause by me incorrectly measuring 3) The new multimeter is a lemon
My plan is to go and buy a new capacitor or two tomorrow and test them with the meter to see what the results are to try to eliminate a few options but I'd like to hear your thoughts.