Hello,
I've lurked this site for a few years now and have found it to be invaluable. But I now have an issue that I can't seem to find, although I've found reference to it. I have a 2005 TL base/no navi that my wife uses and I have been having battery issues after leaving it sitting. The battery was only a year old so I took it back and it tested fine (I can't remember the exact numbers, but it tested "fine"). The HFL had been acting up, so with the help of this site I baked it and that seemed to fix it. After it sitting for another few days though, it died. So I decided just to disconnect the HFL as my wife has a good speaker on her phone.
Since then, I have tested the the voltage between the battery posts with it running and it was 14.2 so it doesn't seem to be the alternator. It starts up fine right after shutting it down and it only seems to die after sitting for a couple of days. I remember the battery numbers were close, and it was Advance auto testing it and I've had bad luck with their batteries before, but it did test fine supposedly, such that they said they couldn't replace it.
I don't know if it's related but it also just started idling funny once in a while, in that when in gear and I turn the wheel or there's a load on the engine, the idle will drop and shudder a bit. I assumed I just needed to seafoam it again but was waiting until before the next oil change.
My next move was to test the battery again but the Advance Auto is a hike from my house and it was supposedly fine so I thought I'd see if there were any other solutions first.
Any other ideas as to what it could be and/or methods to track this down? The inverse of happy wife, happy life is certainly true as well. . . Thanks in advance.

 

your idle is normal, to an extent (keep reading)

Once the car looses power (the ECU to be specific) the engine forgets it's idle. You have to perform the idle relearn procedure. It's very simple. Turn off all accessories such as A/C, radio, lights, etc. Then turn on the car and let it run for 10-15 minutes. The cooling fan should cycle on and off at least twice. Once that is done your idle will be back to normal.

As far as figuring out the parasitic draw, you have a somewhat easy way to do this.

Hook up a multimeter (see how here) Ammeter usage : Basic Concepts And Test Equipment - Electronics Textbook

to the battery in series with the positive terminal. While it's hooked up, DO NOT START THE CAR!!!!

Put it on the Miliamp setting and read the draw on the meter after 10 minutes with ALL the Doors, trunk and hood closed (use long wires on the multimeter) with the ALARM ARMED!!!!

The meter should be reading around 20-30 Miliamps. If it's reading higher then you have confirmed a parasitic draw. To determine what component/system is drawing the power is where the challenge can arise.

You can figure out by removing 1 fuse at a time from the under-hood fuse box and as well the interior fusebox. Remove 1 fuse, close hood, lock doors and wait 10 minutes. If the draw drops to the 20-30 miliamp range, you've found the specific circuit that's drawing power. If the current doesn't drop, replace the fuse and try another one.

Once you figure out what system is draining the battery, you'll have to figure out which computer/module is actually at fault. Sometimes it can be as simple as replacing a bulb while other times it may be as hard as replacing 5-10 parts before you find the culprit!

 

Ok, great thanks. I'll try that and update the post. It was dead this morning after jumping it yesterday and letting it run for about 20 minutes. Usually it wouldn't die with less than 1 day in between. So I'm assuming it might just be the battery going bad as I wouldn't imagine parasitic draws getting worse. I guess it could be the battery just getting worse too from the draw, but may not be "bad." ugh, chicken or the egg . . .guess I'll find out.

Would a bad battery or one that is going bad show a loss as well?
Also, what are the numbers I should be looking for if I do have the battery tested?

Thanks again

 

How old is your battery? That's the first thing. Also take your battery to an auto parts store and they'll test it for you. You don't usually test the battery on your own. They have a computer diagnostics that runs a few tests on your battery (load test, etc.) to see if it's still good. Have you checked water levels ? maybe electrodes are being exposed and have corroded.

 

It's only a year old. It has a 2 year warranty. I already took it to Advance (where I bought it) assuming that it was just the battery. They tested it and said it tested "fine" but I don't remember the numbers they gave me and if I remember right, it was borderline. That's why I am wondering what the numbers I should be looking for are rather than taking their word for it. I think it's a maintenance free battery too BTW. I'm going to do csmeance's test to see if it is drawing but I am leaning toward it being the battery because it seems to have gotten much worse in the past week.

 

Oooh apologies, didn't see that part about battery being a year old. Then yes, check the draw as per csmeance and report back. Ahh the fun of troubleshooting electronic gremlins. good luck!!

 

once a battery gets completely discharged, it can only recharge to about 40-50% max! I believe the engine needs 550 CCA's to start. Running the car for 20 minutes should have recharged the battery. Get a volt meter and check the voltage on your car when it is running. It should be around 14.4V-14.8V when on, and at least 12V when off.

 

I also have a 2005 TL.

Before I removed my HFL I was drawing 160mA.

Afterwards I was drawing 54-56mA.

This was with the hood open, alarm was not armed, everything else was closed. I disconnected the negative battery cable put the red lead on it and the black lead on the battery negative terminal.

Do you think I still have a parasitic draw? From what I have researched 50 mA is the max a car should draw when shut off. I am right around there.

 

it should be around 20ma once you have the hood closed and the car armed after 10 minutes. If not, something else is the root cause.

 

I found the problem to be an iSimple installed to the radio. I removed it. I couldn't close the hood, but the car was armed. I am getting 23-25ma.

I tried installing a working HFL from an 04 TL/NAVI, I have 05 TL non-Navi. I was pulling 130ma.

 

I, too, have recently developed the dreaded dead-battery-after-2-days syndrome with my 2006 TL (with Navi). Disconnecting the HFL module did not solve my problem, so I've had to dive deeper into the electrical system.

After a bunch of troubleshooting, I've narrowed my parasitic draw problem to Fuse #6, and further down to CONNECTOR W on the under-dash fuse/relay panel (and yes, getting to and disconnecting Connector W is a real pain in the a$$). With Connector W connected and the car in "sleep" mode, I measured ~250 milliamps draw at the battery. When I disconnect Connector W, the draw drops to ~30 milliamps.

Looking at the below schematic, it seems that Pin 1 on Connector W feeds the HFL module, the roof console, and a couple of interior lights.

Now it gets weird: If I disconnect all 5 items show in the below schematic, the parasitic draw remains ~250 milliamps. Only with Connector W removed from the fuse/relay box does the draw decrease.

Is there another module in the vehicle fed by this power circuit that is not shown on the schematic. Anyone have any ideas? I can always pull Fuse #6 if the car is going to sit for a couple of days, but this is not a great solution in my mind.

 

I have the same issue on my 05 TL. I already removed HFL. Replaced battery. Still get parasitic draw of about 0.46 amps which varies. Sometimes after i drive my car and if i park it somewhere for 10 min and come back to start it. Turning key doesn't engage starter, everything else works except it won't crank and after getting a jump it starts right up this has happened three times in 3 weeks. About 0.46amps (460mA) if i remove the 40A Backup Acc fuse the draw is next to nothing. Don't know what to do.

 

I have same issue with 40A Backup ACC fuse. Still troubleshooting.

 

Was there ever a solution found to this issue? Having the same problem with my 05 TL 6MT. It's drawing 32.5mA armed, locked and after 10 min? Any solutions out there? Thanks in advanced!

 

~30mA of key off draw might be normal and shouldn't affect your battery unless you leave car sitting for weeks.