04' C5 whoes
Thread Starter
Drifting
Joined: Jun 2012
Posts: 1,391
Likes: 73
04' C5 whoes
OMG, is there an electrical engineer on this forum? Have a drain on my car but I cant seem to get a good reading. Multiple decent meters like fluke but I cant read the drain. I have a fluke dc clamp meter but its crazy. Says 1.43 ma on one scale .143A on another. Milli is 1000 hence 1.4ma is .0014a. Then I tried my flukes in series with the battery. No good. unless you hear the relays on the engine click in its a false reading. So I pulled the fuses one at a time and put them back, yes in the right place but now the a/c fan does not blow and the right window wont go down. Also an error on the DIC about the the steering column. Whats going on. Also the fuse labels are cryptic. How come it cant say 1-int lights.
Racer
Joined: Mar 2017
Posts: 406
Likes: 59
From: Northern California
To read amps you need a dmm in series with the battery. ie remove one battery cable connect one lead of the dmm to the cable. connect the other lead to the battery. put dmm in current mode. forget that clamp meter. get a dmm. oh and get those fuses back in the correct places. 
In the future do one at a time. have all in. remove one. check reading. put back in. remove the next etc.
In the future do one at a time. have all in. remove one. check reading. put back in. remove the next etc.
Last edited by fuggles; Sep 22, 2018 at 08:44 PM.
Racer
Joined: Mar 2017
Posts: 406
Likes: 59
From: Northern California
Yes. Your statement that you tried a fluke in series and you said "no good" means you didn't do it correctly. Its not possible to not debug this issue with a dmm. This is the only way to do it. And yes I am an electrical engineer.,
Thread Starter
Drifting
Joined: Jun 2012
Posts: 1,391
Likes: 73
double negative
" Its not possible to not debug this issue with a dmm"
Sounds more like you are a lawyer with that double negative.
No way to screw up an in serires connection with a meter on current. Other then the meter does nor have a shunt bar. I think thats the only way to really get a good reading, ie shunt bar in series. I dont have one that will read ma, only amps. Like I said, if you dont hear the relays kick in, your meter is really not connected. Try it.
Sounds more like you are a lawyer with that double negative.
No way to screw up an in serires connection with a meter on current. Other then the meter does nor have a shunt bar. I think thats the only way to really get a good reading, ie shunt bar in series. I dont have one that will read ma, only amps. Like I said, if you dont hear the relays kick in, your meter is really not connected. Try it.
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Burning Brakes
Joined: May 2003
Posts: 1,233
Likes: 427
From: LI NY
This tread has some good info about what you should read when checking the battery drain.
https://www.corvetteforum.com/forums...er-3-days.html
https://www.corvetteforum.com/forums...er-3-days.html
Racer
Joined: Jan 2018
Posts: 249
Likes: 49
From: Westcliffe CO
FWIW - If you do everything and still have a drain try this. I spent 3 days trying to pin down a drain with no luck. This was the culprit.
Check your dash dimmer switch and make sure it is not turned all the way to the right past a far-right click position. That will drain your battery if all the way to the right. I had this problem. A tech told me this makes the BCM think several switches are on and it continually sends power to them.
Check your dash dimmer switch and make sure it is not turned all the way to the right past a far-right click position. That will drain your battery if all the way to the right. I had this problem. A tech told me this makes the BCM think several switches are on and it continually sends power to them.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
SEND a picture of the Digital Multimeter that you are using and the way you set it up to measure 0-10 AMPS. That's the only way that we are going to make sense on this issue because there are SOOOO MANY meters and each has it own set up.
Thread Starter
Drifting
Joined: Jun 2012
Posts: 1,391
Likes: 73
Its not operator error, trust me, been doing this before digital meters were invented. Its the shunt in the meters I am sure. So I found a .6 ohm 10 watt ceramic resistor laying around the garage. Thats what a shut is in a meter basically. So I put it in series with the battery and measured the voltage across the resistor. the voltage was .25. Using ohms law I came up with .367mA. Thats close to 1/2 amp, too much. Most modern cars pull 60mA = .060
Billl do you have a c5 blower motor laying around. I would like to see what current other motors are pulling.
Billl do you have a c5 blower motor laying around. I would like to see what current other motors are pulling.
Intermediate
Joined: Aug 2018
Posts: 29
Likes: 9
From: Minnesota
OMG, is there an electrical engineer on this forum? Have a drain on my car but I cant seem to get a good reading. Multiple decent meters like fluke but I cant read the drain. I have a fluke dc clamp meter but its crazy. Says 1.43 ma on one scale .143A on another. Milli is 1000 hence 1.4ma is .0014a. Then I tried my flukes in series with the battery. No good. unless you hear the relays on the engine click in its a false reading. So I pulled the fuses one at a time and put them back, yes in the right place but now the a/c fan does not blow and the right window wont go down. Also an error on the DIC about the the steering column. Whats going on. Also the fuse labels are cryptic. How come it cant say 1-int lights.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Its not operator error, trust me, been doing this before digital meters were invented. Its the shunt in the meters I am sure. So I found a .6 ohm 10 watt ceramic resistor laying around the garage. Thats what a shut is in a meter basically. So I put it in series with the battery and measured the voltage across the resistor. the voltage was .25. Using ohms law I came up with .367mA. Thats close to 1/2 amp, too much. Most modern cars pull 60mA = .060
Billl do you have a c5 blower motor laying around. I would like to see what current other motors are pulling.
Billl do you have a c5 blower motor laying around. I would like to see what current other motors are pulling.
Sorry,, I do not have a blower motor.
BC
Team Owner
Joined: Jul 2012
Posts: 34,479
Likes: 532
From: Central PA. - - My AR15 identifies as a muzzleloader
I believe in the Beer Fairy
Team Owner
Joined: Jul 2012
Posts: 34,479
Likes: 532
From: Central PA. - - My AR15 identifies as a muzzleloader
I believe in the Beer Fairy
It's in parallel till you switch it. That's so the tool takes all the startup load which your meter fuse won't withstand. Then you switch after some stuff starts shutting down and you can check current, obviously, since that's what it's for. Yes I have one in my tool box.
