battery drain on excursion

Further to above, if the const +12V input takes 5mA, check for other drains from the battery. Maybe using the high-Amp (20A, else 10A) for an initial confirmation, and then remeasuring on a mA scale once <200mA is confirmed, the way I do it (on the mA scale) is... - loosen the +ve battery terminal but leave connected. - the -ve terminal can be used instead if the +ve is too difficult or cluttered. - with one test probe on the battery terminal and the other on the battery post (either under, or thru the terminal's post hole), remove the terminal. Hence current continues to flow but thru the DMM. The reason for the above "no break" measurement is that sometimes after a battery disconnect there is a high inrush current upon reconnection (capacitors for some audio systems; other circuits) that could be too high for the mA range. BTW - I have learned to carry spare fuses. Many DMMs use a 200mA or 250mA fuse, typically a "205" (20mm x 5mm) type.

oldspark wrote: I question the +ve lead socket. Usually that furthest left socket is unfused for 10A, or in your case, 20A. The mA ranges use the normal (fused) socket but in your case, the 2nd left "fused mA" socket. The proper socket can make a big difference. IE - a DMM spec'd with 1% accuracy on a 20A scale can mean 1% of 20A = 200mA which means your 5.21mA could be anywhere from -195mA to 205mA. If the 5.21mA is correct, then the drain is ok. 5mA is typical of a LED or less, and 1/50th of a typical Automotive relay or 3W bulb. IOW negligible. (Even some alternators consume over 10mA "parasitically".) And no - you can't get around that parasitic draw. That is the current required to keep the HU's memory and any supervisory stuff (USB connections etc). IMO HUs should have non-volatile memory (that does not require power) for at least tuning (with a reset button). The only issue is if that draw varies - eg, my Alpine which when off draws ~120mA-140mA if BOTH const & switched +12V are connected but only a few mA if only one is connected. Hence I can no longer wire BOTH to +12V like I used to do, and hence the relay that connects the switched to const (whenever it is energised by IGN or ACC +12V, or a manual switch, or the HU's remote output).

oldspark, I will recheck my parasitic draw using the 2nd left "fused mA socket". An aftermarket wiring harness (not sure of the brand) was used to "plug and play" this HU. My question is where should the remote lead "wire" from the amp be connected too? I was looking at deck and I didn't see a reference for this wire? I'm wondering if somehow my jl audio 1000/1 is getting power when the const +12V is connected via the remote lead and its staying on when the key is on the off position? I have included a picture below of the deck wiring diagram. I will upload some additional pictures of where the remote lead is connected to tomorrow if I can find it? This is driving me nuts.....but i appreciate the help I'm getting here. Thanks again 02EX

The HU "remote" is an output to turn on external amplifiers if fitted. I use it to keep the HU power on when IGN is off by keeping the "connect cont +12V to HU switched +12V". But are you sure you have a problem? The 5mA drain is ok. Maybe your batteries dying of age coincided with the new HU and nothing more. A prudent check may be the batteries themselves. I'd assume BOTH were replaced since permanently paralleled batteries (as well as series for 24V systems) must be matched - certainly not new with old. Maybe one battery is defective. A full battery should measure ~12.67V with no load (aka OC - Open Circuit) assuming surface charge has dissipated. (This can read up to ~13.7V and may take 24 hours to dissipate normally, or a few minutes with a load (headlights etc).) If you isolate the batteries (break their +12V interconnection) they should have the same voltage for days (or weeks) excluding any drains. Either or both yous might have drains - eg, alternator's voltage regulator Sense; HU; alarms; central locking.

Here is today's update.... I found out where the blue remote lead "wire' is connected to ....it's connected to what I believe is an orange wire to the factory wiring harness? Here is a picture of the back of the factory wiring harness.. The next pictures are the blue remote lead "wire' from the amp to this orange wire on the factory wiring harness? Remote lead "wire" Does anyone have a clue what this orange wire is? also shouldn't this blue remote lead plug into the deck and not the factory wiring harness? After pulling out the factory wiring harness so i could get a better look at it I've noticed that the previous owner had an aftermarket rear entertainment dvd player and who ever installed it used a combination of quick splice connecters and T-tap connectors onto the factory wiring harness. Yikes! Thanks again for the help 02EX

I checked the following below.... Passenger side battery with the EX off Driver side battery with the EX off Passenger side battery with EX running Driver side battery with EX running Passenger side battery running with the lights and heater on. Driver side battery running with the lights and heater on. The batteries check fine (which they should they are brand new). The DC power alternator also checks fine as well from the volt test and with the draw on it too. Thanks again 02EX

Your charge voltage is too high. It should be a maximum of 14.4V though initial higher voltages may be acceptable. Also interesting the voltage differences between the 2 batteries. 12.58V vs 12.66V means an almost 10% SOC (state of charge) difference. Why? 14.88V vs 14.61V might be too high a voltage drop. However both are too high and therefore maybe higher than normal currents. (14.52V vs 14.48 is still too high and suggests light power is taken from the passenger side/battery.) Definitely check your alternator as those voltages will boil wet cells and ruin sealed batteries. If it has a Sense (S) wire, ensure it is intact and properly connected to the battery +12V. Many Sense wires have a fuse (typically 7.5A even though they only consume tens of mA at the most). (Most alternators go high if the Sense is not connected.) Also check if your battery/engine/chassis ground is ok, tho I expect that to be good since the voltage is more likely to increase with increasing load if there is a bad GND. But when running, check that the voltage across the battery & battery +12V to chassis/body & the +12V supply to the main fusebox (busbar or inputs) are the same or very close.