I got my 2008 Type-S a few months ago and it's been mostly trouble free, but a few little issues are popping up here and there. About a week ago I was on my porch with the TL in the driveway and suddenly the lights in the car just came on and all the doors unlocked. Then today when I was checking my car in the driveway the doors were all unlocked even though I'm certain I locked it last night; I'm always checking for that little red light to be blinking on the door before going inside. In both cases the keys have been inside my house and untouched; I don't live with anyone who would be messing around with my keys. could this auto unlocking have anything to do with the Compustar remote starter the previous owner had installed? That remote starter hasn't been much good to me either since it's almost never able to start the car in cold weather. More than anything right now though, I'm thinking I'm going to have to stop leaving any valuables at all in my car.

 

Take a multimeter and check your battery when the car is off. If the battery is failing it could do that. Also you say you were never able to start the car in cold weather. It gets down to -25F here and cars still start properly if the battery and alternator are in good working order.

A faulty door actuator can also do that. But check the battery first.

 

I haven't heard of this but a dying battery has been known to manifest itself in all sorts of odd electrical issues.

 

if you can start the car in cold weather and the auto start cant there is something wrong. I suspect battery too

 

Finally got hold of a multimeter to check the voltage on the battery. It's only reading around 10.10 while the car is off. It's a Duralast that the previous owner claimed he had put in this past February. Kind of unusual for a battery to be dying after less than a year, isn't it? Either that or the previous owner wasn't being entirely truthful. It would be nice if this problem is as simple to fix as getting a new battery, but I can only hope I won't find any other unpleasant surprises. The pre-purchase inspection I had done on this car came up good.

 

a good battery will test 12.2-4 volts

usually there is a born date sticker on the battery. and im assuming you didnt see one, or would have noticed it.

 

Battery should have been tested in a thorough pre-purchase inspection. As well as alternator.
This is done in the same way, which is hooking a multimeter to the battery while the car is off and while the car is on to get a charging reading (alternator) + no charge reading (battery).

justnspace got that right. Furthermore, a proper working alternator should test out at 13.8V to 14.2V more or less. Battery should never dip close to 10V unless it's discharged. Brand spanking new it's possible to test it out at 12.6V. While charged it should never test under 12V, otherwise you need to change it.

I advise you to change your battery as soon as you can to avoid putting useless strain on other electrical components. It might not solve your door problem, but it sure hurt!

 

Spend roughly $100 for a new battery and as polobunny has mentioned, it might not fix your issue but it's not going to hurt to have a properly charged and working battery under your hood.

 

The 24f battery size wasn't available at Costco so I went with an Everstart Maxx and it's started the car perfectly since I got it. I've been pleasantly surprised to see the remote starter actually working reliably. Unfortunately, the doors are still occasionally unlocking themselves.

Any suggestions as to where to go from here would be much appreciated. I've never taken a car to a dealership for service so I have no idea what to expect or how they might try to rip me off. When I recently called an Acura dealer to get an idea of price range to fix this, they told me it would cost $115 just to have the car looked at.

 

What model of compustar? My bet is that it's the cause (or complementary door lock module that was installed with it). Pull the power to it for a few days and see if the issue continues.

 

The $115 is likely an hour of labor. If you have after market / non-OEM parts on your car, save yourself the $$ and do as nfnsquared mentioned. Once the dealership finds your Compustar, they will automatically say that is your issue-which it may be.

 

You might consider resetting your keyfobs to make sure you have the only keys to open the car. A reset will cancel any others. There's a great video on you tube that shows you how to do it.I did it as a precaution on my '06 since I wasn't the original owner.