Ideal 61-340 not power on with T<20 C, how to disassemble?

[ulyanoff]

Hello all! Strange device, works only in a warm room with a temperature above 20 ° C (68 ° F), all measurements being accurate. As soon as the temperature is low, for example, it simply does not turn on. Tried the body for bending, tapping in various places - to no avail, also replaced the battery with a new one - it did not help. Please help, can anyone know how to disassemble it? having unscrewed screws the case does not open, because it holds the central switch. Maybe a secret?

[CustomEngineerer]

On the backside, there are 2 screws along the bottom, and a third under the tilting stand. You have to pull the stand all the way out to access this screw.

[beanflying]

What sort of batteries are you using in the meter?

Some NiMh batteries have very poor low temperature characteristics, there are specific low temp ones available. If you are using them see if you can still source NiCads which are much better even in sub zero temperatures.

Even primary cells don't like low temps either or it may of course be the meter

[ulyanoff]

We continue. All the same I dismantled it. for those who will do it, I want to inform you that the switch itself is not needed to be removed. I do not have this it turned out, and I thought that he was holding all the fees. In fact, simply the board is tightly "seated" in the case, and is removed separately from the switch.
Then he carefully inspected the damage, washed the remnants of Chinese flux. Selectively checked capacitors on ESR / 10?f x25 v showed ESR 15 ohms.
The problem has been determined. Then replaced by 10 ?f x16v, there were 4 of them. (at 25 v in was not at hand). After soldering, he washed everything off the flux. After assembling the multimeter
works in a cold room !! . While on testing. Here's a photo, it might be useful for others.
p.s. I hope this helps!

[WaldoP]

I know this is an old topic, but I'd like to thank you for your work here. I hadn't associated the seemingly random failure of my 61-340 with temperature, which is almost constantly in an environment of between 18 and 21 degrees.  Once I saw your post, and head-slapped myself, I realized that it was temperature-sensitive, and the solution was obvious. I had one cap w/ ESR=16, and like you, I replaced all four. Meter is fully functional after an hour in a refrigerator, so it would appear that it is all good now.
I cannot thank you enough.

-Random cold-meter guy.