# Fluke 77 Multimeter stopped reading current

#### bluebrakes

Joined Oct 17, 2009
251
Hi,

my old faithful fluke 77 multimeter has stopped reading DC and AC current.
It still reads Ohms, Volts and continuity, just not current.

I found this guide here...
http://assets.fluke.com/manuals/75_77___omeng0900.pdf
although it doesn't help that the 77 pcb is slightly different to the diagram shown. i.e. I don't have a couple of the components or two fuse holders in mine.

With components being tested with another multimeter still on the fluke 77 pcb, nothing seems to be faulty. I checked the fuseable resistors and i can't seem to find anything faulty.

Has anybody else had this problem or know what component could be at fault?

Thanks.

#### bluebrakes

Joined Oct 17, 2009
251
photo attached of my fluke 77 board.

#### Attachments

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Joined Jul 7, 2009
1,583
The cause for not reading current is usually one or more blown fuses, especially if the other functions work. Since your PCB doesn't have fuse holders, then the fuses must be less obvious components -- maybe you should do a continuity test on all the components.

#### t06afre

Joined May 11, 2009
5,934
Take a look from page 27 and out in your manual. I think I see one empty fuse holder in the picture. But you should have 2 fuses. And I can not see the the small fuse holder at all

#### wmodavis

Joined Oct 23, 2010
739
You likely left the red probe in the 10A or 300mA and tried to measure a voltage source that when presented with a near short circuit, dumped enough current into the meter to blow the replaceable fuses.

#### praondevou

Joined Jul 9, 2011
2,942
this fluke77 looks different, like in your manual... why? sure your is a 77?

#### hgmjr

Joined Jan 28, 2005
9,029
Make sure you replace the fuse with the proper Fluke fuse.

hgmjr

#### Jaguarjoe

Joined Apr 7, 2010
767

#### t06afre

Joined May 11, 2009
5,934
Hmm.!! Where can I find fluke fuses.
I need plenty, cause I use like what comes my way.
If you use fuses from a well known manufacturer. That are approved. And follow the spec from Fluke. You should be OK. But using no branded simple glass fuses. May not be the best.
I often use fuses from littelfuse http://www.littelfuse.com then I need fuses I can trust. I think my Fluke came with a littelfuse fuse for the hi amp range