Parasitic Draw

[Akelenfo]

I’m checking the parasitic draw on my car battery and am confused as to the displayed data; is the draw in Amps or Milliamps? The readings were taken just the rotary dial changed; its suggested the draw should not exceed 50mA and based on one image and the setting it looks to be a draw of 20.3mA which would mean everything is good. Then the second image shows 2.06 but I’m not sure what this is? Can anyone explain the two readings and am I correct in saying it is 20.3mA draw I have and not 2.6A? Please refer to the rotary settings. Thank you.

 

[telectrix]

you have your red lead in the 10A range socket. your mA readings will not be accurate.

 

[Akelenfo]

Thank you, but I’m none the wiser. To check the draw on the battery, the lead should be in the 10A and the rotary dial at 10? If this is correct then the image is showing a draw of 2.06A, would this be correct and this would be an unacceptable draw on a battery?

Thank you.

 

[James]

How have you connected the leads to the battery?

 

[Akelenfo]

The red probe is connected to the earth lead of the car which is disconnected from the battery; the black probe is connected to the negative terminal of the battery thus putting the current through the meter. The positive side of the battery remains connected to the vehicle.

 

[telectrix]

your meter should have the red lead in the hole below to measure mA, on the 200 mA or 20mA range. your 2.06 is amps, so something is drawing current when you measured that on the 10A range.

 

[Akelenfo]

Thank you, you’ve been most helpful; I’ll now start to trace the draw by systematically removing fuses from the boxes.

Have a great evening.

Regards,

Allan

 

[gyislander]

Don't forget that you need to give the car time to go to sleep before you start testing and that includes after taping the bonnet switch shut as well as any open doors. Otherwise there will be some draw all the time giving you a false result

 

[Akelenfo]

Thank you; I’ll be running the test today and will apply your advice before starting.

Very much appreciated.

Allan

 

[sam400]

You can do a parasitic draw test by measuring the volt drop across each fuse, then cross referencing to this chart.

 

[Akelenfo]

Good afternoon all,

Update: My car is a Ford Crown Victoria Police Interceptor and has a lot of equipment installed. If you recall the draw was 2.6A, way above the acceptable level. I found the K9 Hot n Pop system had a 1A draw whilst the car slept as the K9 system remained active to look after the dog. Switching off the isolator sorted this. In addition the trunk had a mercury switch as did the hood and when closed dropped the draw by another 1.34A as they also ran equipment whilst the car slept. All these issues have now been resolved and the draw is a comfortable 0.26A, well under the maximum acceptable limit. Just wanted to update you all, thank you for your advice and guidance and I wanted to bring this to close.

Very best regards,

Allan

 

[DPG]

Nice one! And nice car.