Parasitic draw testing blew my fluke meter 10a fuse

[snafu]

Blown fuses in the fuse box indicate a short (penny in the 12v socket), excessive current draw (plug a 30A accessory into a socket wired for 15A), etc..  That could be an entirely separate issue.

You made a simple mistake testing for parasitic draw and it cost you the fuse in your 115.  Unfortunately, you may have to order one.  Here's what you should have done after disabling the trunk light:

1 - Remove the negative terminal from the battery

2 - Hold the negative terminal against the side of the negative post of the battery, allowing the vehicle's accessories to normalize - this can take a minute or even longer

3 - While you are holding the terminal against the post, clamp the black probe to the negative post on the battery and the red probe to terminal on the battery cable (probes set up for alligators make this easy)

4 - After things have normalized, separate the negative terminal from the battery post, watching the display of the DMM closely - if it's over 10A, you need to very quickly get the terminal back in contact with the post to avoid blowing another fuse

5 - Assuming the reading is under 10A, you can begin troubleshooting with the 115.  If it is over 10A, you'll need access to an i410 current clamp to begin the process.  

Yes, you have the correct tool for troubleshooting parasitic draw and the 115 is a fine meter.  50mA of parasitic draw is considered the maximum acceptable.  30mA or less is ideal.  Yes, you remove / replace one fuse at a time in all fuse boxes (under dash, under hood, etc) in an effort to determine the circuit responsible for the draw during this process.

Unfortunately, a "dummy light" or incandescent test light is not the tool for this job.  While it will light up showing draw, you cannot determine what is acceptable / unacceptable from its level of brightness.  However, it could be used in lieu of the i410 should current draw be over 10A to begin with.  You simply clamp it to the battery post and connect the terminal to the cable.  Once you've found the source of the BIG draw, then substitute your 115 to verify maximum parasitic draw is less than 50mA.

[06RTCharger]

4 hours ago, snafu said:

Blown fuses in the fuse box indicate a short (penny in the 12v socket), excessive current draw (plug a 30A accessory into a socket wired for 15A), etc..  That could be an entirely separate issue.

You made a simple mistake testing for parasitic draw and it cost you the fuse in your 115.  Unfortunately, you may have to order one.  Here's what you should have done after disabling the trunk light:

1 - Remove the negative terminal from the battery

2 - Hold the negative terminal against the side of the negative post of the battery, allowing the vehicle's accessories to normalize - this can take a minute or even longer

3 - While you are holding the terminal against the post, clamp the black probe to the negative post on the battery and the red probe to terminal on the battery cable (probes set up for alligators make this easy)

4 - After things have normalized, separate the negative terminal from the battery post, watching the display of the DMM closely - if it's over 10A, you need to very quickly get the terminal back in contact with the post to avoid blowing another fuse

5 - Assuming the reading is under 10A, you can begin troubleshooting with the 115.  If it is over 10A, you'll need access to an i410 current clamp to begin the process.  

Yes, you have the correct tool for troubleshooting parasitic draw and the 115 is a fine meter.  50mA of parasitic draw is considered the maximum acceptable.  30mA or less is ideal.  Yes, you remove / replace one fuse at a time in all fuse boxes (under dash, under hood, etc) in an effort to determine the circuit responsible for the draw during this process.

Unfortunately, a "dummy light" or incandescent test light is not the tool for this job.  While it will light up showing draw, you cannot determine what is acceptable / unacceptable from its level of brightness.  However, it could be used in lieu of the i410 should current draw be over 10A to begin with.  You simply clamp it to the battery post and connect the terminal to the cable.  Once you've found the source of the BIG draw, then substitute your 115 to verify maximum parasitic draw is less than 50mA.

THANK YOU SNAFU! Thats a great technique for getting the dmm inline without causing the battery to think its being disconnected and reconected, i appreciate it. Ill be doing this today soon as i get off work. Ill also be checking over the outlet to see if some small metal prong or something is jammed inside, looks fine when i seen it.

[snafu]

4 hours ago, 06RTCharger said:

THANK YOU SNAFU! Thats a great technique for getting the dmm inline without causing the battery to think its being disconnected and reconected, i appreciate it. Ill be doing this today soon as i get off work. Ill also be checking over the outlet to see if some small metal prong or something is jammed inside, looks fine when i seen it.

You're quite welcome.  Let me know what you find.

[06RTCharger]

On 6/16/2017 at 4:27 PM, snafu said:

You're quite welcome.  Let me know what you find.

Alright i was able to use ur technique and it worked perfectly man, THANKS. Had to go find some fluke aligator clips so only got to do it today. Just checked the draw and it was 0.012-0.011 amps. Google calculator said thats 12 milliamperes, sounds right. My meter doesnt have the millamp setting just millevolts. So there is no draw right now, BUT i havent replaced the fuse for the cigarette lighter/power outlet. 

Snafu what would the voltage drop mean on that cigarette lighter? When i set my meter to millivolts, i think its reading voltage drop because when i touch probes together it reads 0 and when i touch all the other good fuses it starts at like 2mv then zeros out in a second or two. BUT with the cigarrete lighter fuse spot it reads 4-3.5 millivolts when i stick the probes into the two fuse sockets. Also that is a selectable power outlet, u can set the fuse in one spot and the lighter will only work with the car on and the other spot it will work with the car off. The 4-3.5mv is with the spot that needs ignition on. When i test the drop on the "no ignition" spot it reads 25-26 mv? Is that normal because its a power outlet? So i went and removed the whole lighter assembly, and pulled the plug out from behind the lighter outlet. I tested for v drop on that plug and it reads a 12.5mv drop. All these reading are with NO FUSE in the fuse box and cigarete lighter assmebly completly removed. Is this normal? If not what do i look for next? I know its not as simple as replacing the cig assembly becuase the drop is there without it even connected. Does it sound like a ground issue? Does a bad ground sound like the culprit? Gonna try to hunt down the ground for that cig lighter just to see how it looks. Thanks for helpin me out, sorry for all the questions lol u can just answer the main points you feel are important. I just try to give the most info i can so i can give the clearest idea of whats going on with my car so its a lil easier for ya'll to help me out.

Shopping tip for memebers here, Turns out a local sears is one of the best places to buy fluke stuff. I paid 240 for my fluke 115 at Napa auto parts. Sears was only 180, regular price. They also have all kinds of attachments and some carry cases. Thinking about picking up the fluke current clamp for them too for later. To Clamp my amps and test what their pulling and all that kinna stuff. 

[snafu]

Glad you were able to make a solid analysis.  Yes, that is 12mA (12 thousandths of an amp) - so, well below the maximum threshold of 50mA.

On to your voltage drop measurements . . . 

You can't measure voltage drop in that fashion.  Voltage drop measurements are conducted across components of a circuit with the circuit under load.  For example, you want to determine the voltage drop over the length of cable from your battery (+) terminal to your starter.  Set your DMM to measure DC Voltage, probes in "normal" locations.  You connect the RED probe to the battery (+) and the BLACK probe to the starter stud.  Then, you set your 115 to record voltage over time by pressing the MIN/MAX button.  Then, you start the vehicle.  After starting the vehicle, you press the MIN/MAX button on your Fluke to scroll through MIN, MAX and AVG readings until you see the MAX reading.  This will tell you the voltage dropped (lost) over the length of cable while you were starting the engine.  Now that you have some alligator leads, give it a whirl and you'll see just how easy it is.