When I bought my 2010 Odyssey EX about a year ago it came with a Chinese Android replacement radio. I didn't realize at the time it wasn't the OEM radio, although I was surprised by a 10" touchscreen in a 2010 car. More recently, in chasing an issue of parasitic current draining the battery with the car off I discovered that these radios often continue to draw significant current after the car is turned off. As such I expect this is of interest far beyond the Odyssey community, but this was the most convenient place for me to post. BTW, the large parasitic current I was chasing turned out to be the inside lights remaining on because one of the sliding doors remained slightly open, not the radio.
To chase down the parasitic draw I disconnected the negative terminal of the battery and inserted a multimeter with a 10A scale in series. By pulling fuses, beginning with the 120A/70A double fuse and checking the change in current draw, and following the path from there through other fuses I quickly found my way to the interior lights and the slightly open door. But even with that dealt with (I just turned off the switch at that time) I still had significant current draw, partially via fuse 5 (driver's side fusebox) going to the radio and also fuse 7, controlling the sliding doors (among many other things). By watching for a little longer I discovered that the sliding door parasitic current of several hundred ma only continued for about 10 seconds and then dropped to a few 10s of ma. So the interesting part of this story is the radio.
The radio drew about 500 ma or so, apparently indefinitely, or so it appeared. That isn't enough to drain the battery overnight, but it will drain it in less than a week, so I set out to deal with it. A quick look at the internet found many posts and youtubes about this parasitic current. Apparently these Chinese android units (from many different suppliers) have a "sleep mode" which can be set to as little as 2 hours, but in other units can only be set to 1, 2 or 3 days, and 2-3 days is enough of a hit to the battery that they should be avoided. I couldn't find a way to select the sleep mode duration in my unit, but I found other posts referring to a way to choose one of several modes via the "engineering test debugging" option under "factory settings" where sleep mode could by entirely bypassed vis the "direct shutdown mode". The problem is that if sleep mode is fully disabled, the rado does a full boot of the android OS when the ignition switch turns it on, requiring 30 seconds or so before the radio (or anything else) does anything.
Finally getting to my revelation (I didn't see this in any other post), I decided to try the "direct sleep mode" in the set of debugging options. I set up my multimeter on the 10A scale in series with the battery's negative terminal using clip-leads so it would remain powering the residual current to the car with the ignition switch off (via the shunt resistor in the multimeter), even of the meter turned itself off. Now I could watch for changes in the parasitic current drawn by the radio by ocassionally turning the meter back on and checking the current. It turns out the current remains at about 500 ma for about 2 hours but then drops down to about 20 ma or so. Drawing 500 ma for 2 hours is only a 1 Amp-Hr hit to the battery, a small fraction of its capacity. The good news is that the radio comes on essentially instantly after this, even though the radio wasn't drawing the 500 ma from sleep mode for many hours after that. So this looks like an ideal solution.
Frank
To chase down the parasitic draw I disconnected the negative terminal of the battery and inserted a multimeter with a 10A scale in series. By pulling fuses, beginning with the 120A/70A double fuse and checking the change in current draw, and following the path from there through other fuses I quickly found my way to the interior lights and the slightly open door. But even with that dealt with (I just turned off the switch at that time) I still had significant current draw, partially via fuse 5 (driver's side fusebox) going to the radio and also fuse 7, controlling the sliding doors (among many other things). By watching for a little longer I discovered that the sliding door parasitic current of several hundred ma only continued for about 10 seconds and then dropped to a few 10s of ma. So the interesting part of this story is the radio.
The radio drew about 500 ma or so, apparently indefinitely, or so it appeared. That isn't enough to drain the battery overnight, but it will drain it in less than a week, so I set out to deal with it. A quick look at the internet found many posts and youtubes about this parasitic current. Apparently these Chinese android units (from many different suppliers) have a "sleep mode" which can be set to as little as 2 hours, but in other units can only be set to 1, 2 or 3 days, and 2-3 days is enough of a hit to the battery that they should be avoided. I couldn't find a way to select the sleep mode duration in my unit, but I found other posts referring to a way to choose one of several modes via the "engineering test debugging" option under "factory settings" where sleep mode could by entirely bypassed vis the "direct shutdown mode". The problem is that if sleep mode is fully disabled, the rado does a full boot of the android OS when the ignition switch turns it on, requiring 30 seconds or so before the radio (or anything else) does anything.
Finally getting to my revelation (I didn't see this in any other post), I decided to try the "direct sleep mode" in the set of debugging options. I set up my multimeter on the 10A scale in series with the battery's negative terminal using clip-leads so it would remain powering the residual current to the car with the ignition switch off (via the shunt resistor in the multimeter), even of the meter turned itself off. Now I could watch for changes in the parasitic current drawn by the radio by ocassionally turning the meter back on and checking the current. It turns out the current remains at about 500 ma for about 2 hours but then drops down to about 20 ma or so. Drawing 500 ma for 2 hours is only a 1 Amp-Hr hit to the battery, a small fraction of its capacity. The good news is that the radio comes on essentially instantly after this, even though the radio wasn't drawing the 500 ma from sleep mode for many hours after that. So this looks like an ideal solution.
Frank
