[flexed]

Okay, my friend has a 08 honda pilot ex-L. Having issues with the battery draining. Changed out the old battery still doing the same thing. Does any one know what the thing is that looks like a phone jack on the diagram and in the other picture is 3 wires coming out of it and is all rusted?? AutoZone claimed its not supposed to be there.

 

[Pilot2003_1]

That would be your ELD unit. Do you have a code thrown for it? If not I have my doubts it’s bad. I believe that brown rust is just dialectic grease from the factory.

Honda has what’s called Electronic Load Detection. When the electronics aren’t drawing a lot of power, it drops the charging state of the alternator to ~12ish volts. When things like the AC or ignition system draws more current it will switch on the alternator to 14V+. That brown box detects the current going through the fuse box. This system was designed to reduce load on the motor and squeeze out a little more MPG.

What brings you to the conclusion of having a parasistic drain somewhere? If it’s just a guess I’d recommend you follow my guide I put together to diagnose the charging system. My hunch is you’re having a charging issue somewhere.

Charging System Diagnosis Guide

Since I've been having charging problems and I narrowed it down to the alternator I figured I'd organize everything I documented and written down and put together a guide on diagnosing the charging system. Charging issues seem to be a common problem around here and these cars are a little...

www.piloteers.org

 

[aggrex]

Okay, my friend has a 08 honda pilot ex-L. Having issues with the battery draining. Changed out the old battery still doing the same thing. Does any one know what the thing is that looks like a phone jack on the diagram and in the other picture is 3 wires coming out of it and is all rusted?? AutoZone claimed its not supposed to be there.

Get the Pilot charging system checked at your local Advance/Autozone. Inquire whether any new devices have been added like an alarm system or whatever and whether the battery issue is a recent or ongoing problem

 

[EA_SF]

Agree with getting it checked. If you're saving up for repairs, this would be a good temporary solution to avoid parasitic drains in the meantime imo.

 

[road2cycle]

If you have a multimeter you can easily check the state of the charging system. Verify battery voltage is ~12.6Vdc after the Pilot has been turned off for a few hours. If lower than ~12.4Vdc I would charge the battery with an external charger before continuing.

After battery has been verified as fully charged, measure voltage across the battery when the Pilot is on but all major loads (A/C, headlights, cabin blowers, etc.) are off, then measure the same when the loads are on. First measurement should be ~14.4Vdc and second measurement should be ~14.2Vdc.

If all that checks out then you can start looking for parasitic draws. There are a couple methods for testing that. Pilot is turned completely off when doing this. Either measure mVdc (millivolts) across each fuse (fuses with highest measurements indicate potential problem circuits) or disconnect battery negative and put meter (in current measuring mode) between battery negative and the battery negative cable. Pull fuses one at a time and look for a significant drop on the meter. Once you’ve identified the problem circuit(s) then the fun part of debugging begins.