Parasitic drain in 2005 Acura TL

acura
tl

#1

What experience have u had with parasitic draining? Who in the San Francisco Bay Area best treats this? Is it worth fixing this in a 2005 Acura TL? Love tha majestic TL…


#2

Some TL owners have had issues with the bluetooth phone module and parasitic drains. Could pull the fuse for that and see if it goes away.


#3

I’m far from an expert, but I had a parasitic drain last summer. After some research, I found the following video to disconnect the hands free link module and haven’t had any problems since. https://youtu.be/8BJTQK0TNYA


#4

I don’t think you have them out there but the seat heaters were also a problem on the TLs.


#5

If you have a volt meter, you can test for drains pretty easily. There’s 2 methods you can use, depending on how anal you are about keep-alive memory and module settings.

With your volt meter, take the + and - cable leads and touch them across the two terminals of every fuse in your car. Measuring DC voltage, any circuit with current flowing through it(parasitic drain) will show “some” sort of reading, usually about 0.04v or thereabouts. Any fuse with NO current flowing(no draw) will read 0.00v. The reason for this is that volt meters are not actually reading specific voltage capacities, they are actually reading the difference in voltage between the two leads. What you’re doing is called a voltage drop test, but on a very tiny portion of the circuit, so you need to have an accurate meter. Voltage won’t vary across circuits with no electrons flowing.

The 2nd method is admittedly easier to determine what circuit is affected, but it comes with the caveat of having to unplug every fuse which could affect some modules in some cars.
With your multi meter setup to read amperage, disconnect the negative terminal of your battery, and place the meter leads in series with those connections. Positive lead of your meter hooked to the negative cable, negative lead of your meter hooked to the negative battery post. This will place the meter in-line on the amperage return path and will accurately show you the draw on the battery, and you can watch the meter while unplugging fuses to find the circuit that has the draw.

Maximum acceptable draw on most cars is 50 milliamps, or 0.050a. Most cars will have quite a bit less than that.


#6

Except that most cars will read high, several hundred mA, until all the computers go into the sleep mode, which takes some period of time, perhaps an hour. If you disturb anything, like opening a door, they come out of sleep mode and you have to wait again.


#7

One other issue I have run into is regarding in rush current. The proliferation of electronics doodads has also increased the total amount of input filter capacitance on the vehicle’s DC bus. In consumer electronics, design provisions are often put in place to limit in rush current as all these caps place a heavy demand on the power supply. In a car, there’s a monster battery so they perhaps don’t see a need to do that. My favorite DVM has a 10A fuse on DC Amps. Even with a slow blow fuse, I was occasionally blowing the meter fuse when reconnecting the car battery. So I made a shunt from some large gauge wire to short out the meter leads during the initial inrush. Once everything had settled out (~5sec or so) I would disconnect that wire and then the meter was in circuit. By then the normal current was ~200ma and then would drop a few minutes later as the modules went to sleep.