This 2006 Acura TL came in with the complaint that the battery would go dead while the car was parked and not being used. The first thing that I found was a dead cell in the battery but I wanted to cover all the bases and checked for a drain condition. I installed my trusty Fluke meter in series between the negative battery post and the negative battery cable. With the meter set up to read DC amps, I found that there was a constant .25 amp draw and it would cycle up to about .65 amps every now and then.
I pulled fuses one at a time in the underhood fuse box until I discovered that by removing the #15, 40 amp PAL fuse, that I am pointing to in the next picture, the drain would go away.
I checked the wiring diagrams and found that fuses 5,6,7,8 & 9 in the interior fuse box are all powered by fuse #15 in the underhood fuse box. By removing them one at a time I found that the problem was on the number six fuse circuit.
That fuse powers multiple interior lights and the Hands Free Link module, HFL. I could see that there were no lights on, so I wanted to check out the HFL. The HFL is supposed to be in the overhead console. The first step to locating it is to remove the power sunroof switch as shown below.
Depress the latch to disengage the harness connector from the switch.
Then I had to reach into the cavity and firmly pull down on the black housing.
This disengages the spring clip just above my thumb.
Remove the harness connector from the lighting panel.
I can now see the HFL module but not the connector.
There are four 8 mm headed screws that hold the trim panel in place.
With those removed the panel will come down and there is the HFL module. By the way it was warm to the touch. The customer stated that she does not use the HFL and was not interested in replacing it. I mearly disconnected it and positioned the connector out of the way.
I also found that an easy test for this problem is to touch the windshield just above the rear view mirror and see if it feels warm. Granted you would have to so this on a cool vehicle, in the shade, with a fully charged battery.
I found that the module would also cycle up to 2.2A for ~7s every 30s or so if you wait for a few minutes. This draw was draining my battery every time my TL sat for around one week. Disconnecting the module dropped baseline current flow to only ~50mA. Thanks for sharing this guide.
Start over again with the basics. Have the battery fully charged and retested. Install an amp meter in series with a battery cable and check for the size of the drain and if one is present.