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Also suspect a parasitic draw. Been documenting the battery voltage day by day. I want to see how long it last unhooked vs when I hook it back up. For now saving money trying to get threw the year.
Not sure monitoring voltage is going to help with that. Accepted method is a an ammeter between a battery post and its lead. Once the first current spike (energising electronics) is past, you can then see if there's a current draw higher than there should be. I went through all this with a duff multimeter earlier this year as the battery had drained down twice over - but with little provocation.
Working on the truck last week re-wiring front turn signals so had the turn signals, hazards, and parklights on here and there as I checked my progress and had the brake lights on for a very short period also. None of the above were left on longer than necessary but the next day the truck wouldn't start - wouldn't even turn over. On a plug-into-the-ciggy-lighter-socket-voltmeter it showed 11.7V. As did the brand new replacement battery when first installed. Admittedly today following a decent (130 mile) run yesterday the new battery is now showing 12.2V but a battery that can only be considered as fuct showed the same voltage as a brand new one.
That's true. I have a multi meter but not sure how to test millivolts. I originally wanted to test the system with the meter reading millivolts and start pulling fuses til the number dropped. But I dont think my meter reads that. It's a commercial electric
It's Amps you want to be measuring - on your meter use the setting one click clockwise and the connector port on the left. If you need greater sensitivity, mA is the next click round and the port on the right.
Remember though you are looking to measure a small parasitic current - so everything has to be switched off - including lights operated on door opening. A parasitic draw should still be less than 1Amp so readable on your Amp scale. Your mA option is limited to 400mA which isn't quite half an Amp.
Never forget the current is flowing through the meter when you're measuring it so don't allow it to become excessive - fused or not.
That's what makes me nervous lol. I've already blown 1 fuse a while back lol. So heres my issue. If everything off like accessories. My alarm and hood lights kick on. I can unplug the hood light. But the alarm can only turn off if I use the remote. So am I not able to test the system?
Disconnect the hoodlight.
Use the remote to turn off the alarm and then disconnect the battery and hook up the MM? Or does doing that set the alarm off?
I've never had to deal with an alarm system but they are notorious for dragging batteries down. When yours goes off (assuming it going off here is the cause for concern) does it flash lights, sound the horn, that kind of thing - creating current higher than the MM's limits?
If it is the disconnection of the battery and reconnection with the MM that is the problem - there is a way around that.