05 CDI parasitic drain

[dieselbenz1]

I initially thought I had a weak starter as every cold morning the engine was slow to turn over. I left it for 4 days then I got the red warning message to charge the batteries. So while charging the batteries I checked the current draw on all the circuits which totalled 30 mA from 3 circuits so that looked normal. I noticed a blue tooth third party connector in the glove box. I would like to remove that device whih I would assume is behind the glove box. I haven't a clue how to remove the glove box but while looking the radio came on and then the climate control started blowing air all with the key out of the car but passanger door opened. Also I had manually turned them off when I shut down the car. I'm just looking for ideas on where the blue tooth maybe hiding or what is really happening.

[dieselbenz1]

Last evening I located the third party blue tooth device behind the glove box so I removed it. I will check the condition of the battery latter this morning kind of chilly out now -18 C.

[Diseasel300]

4 days seems an awfully short period of time for a 30mA current draw to deplete a battery. How old is the battery? It may be time for a new one.

[Grzpdlr]

Originally Posted by Diseasel300

4 days seems an awfully short period of time for a 30mA current draw to deplete a battery. How old is the battery? It may be time for a new one.

Recently had the same problem with my 05 e320 cdi of parasitic drain. Turned out to be the cheap Chinese radio I installed. From what I read the radio is most often the culprit.

[dieselbenz1]

The battery is 6 months old, the 30 mA current draw was just measured one time. Since the stereo and maybe hvac would randomly turn on and off while the key was out that would explain the battery draw being much greater than I observed. Time for a data logger to capture events like I experienced. A quick check this morning 12.4 v exactly the same as I had left it 10 hours ago. Getting more confidence that was my problem now I just want to double check on how it was wired into the sysrem.

[dieselbenz1]

Well this was by far the best cold morning start I have ever experienced in this car. The starter sounded like a healthy starter should. So far I have just eliminated the 3rd part blue tooth, mObridge model abt2010 but the power connections appear to follow the ignition switch, arrrrg.

[jay_bob]

Double check you don't have moisture intrusion into your central gateway (ZGW) module under the drivers side dash cover, or the rear SAM in the left side of the trunk.

The key switch on the 211 and later model switches very little actual power to devices. Most of the equipment in the car is connected to constant voltage and only gets its command to run from CAN bus messages (or the pink Wake Up wire for audio devices on the MOST bus as I indicated in the other thread).

If your CAN bus is having issues, then you could get intermittent energization of the systems in the car.

The converse is true. When my son was having all the issues with the CAN bus, things would start randomly turning on and off while going down the road.

https://www.peachparts.com/shopforum/diesel-discussion/400578-w211-can-bus-problems.html

[dieselbenz1]

Thanks Jay_bob rear sam is dry, no codes at all, I will check ZGW. You made mention of the halo around the speedo now on at all times the cruse is engaged. My halo disappears after a minute also strange is when I turn off the car but switch it back on to position 1 to listen to the radio it takes several minutes before the radio turns on.

[dieselbenz1]

Well I still seem to have a random current drain. Tested alternator under load today just watching voltage 14.0 after 10 minutes minutes starts at 13.6. Turning on all loads on highway voltage will dip to 13.8. No AC component so should be good. With the radio fuse out the blue tooth out something is turning on and off the hvac unit. Can't even identify which fuse it is connected to. Needed to reconnect blue tooth as removing it kills the command module. Really the MOST bus has a missing component so the command unit shuts down WTF.

Found the gateway but its looking clean debating disconnecting batteries and clean all communications connection points in I believe 3 areas. Its just a pain resetting everythig afterwards so want to do as much as is reasonable.

[jay_bob]

If I remember correctly that type of Bluetooth unit sits in the MOST ring.
Did you reclose the fiber ring after taking out the adapter?

[dieselbenz1]

Its actually not in the fiber ring but connected to the aux input. I believe once the can bus is disconnected the command module freaks.Its almost as if its somehow configured in the command module.

[jay_bob]

They must have tied into the CAN to get the steering wheel button data then.

What is the name of the Bluetooth unit? May be able to do a search for the install manual for the device online. That may have a clue as to what was configured in the head unit to make the steering wheel buttons work.

I know there is a hidden Engineering Mode menu for these head units. Don't remember the 3 keys you have to hold at the same time but it's all over YouTube.

[dieselbenz1]

The blue tooth unit is mObridge model abt2010, I will have a look at configuring the command unit.

[dieselbenz1]

Radio 28, command unit 6 and cd fuse 26 pulled I was able to capture something causing a 8 amp load which turned on at random while key out doors closed trunk lid opened all lights off. I was testing why the current drain is showing as .25 amp and found fuse 9 sunroof was causing half of this draw. 15 minutes into testing I noticed the drawbut could not see or hear anything related.

[dieselbenz1]

Testing by pulling fuses is rather frusterating as the total draw fluctuates from 40mA up to 3.3 amps sometimes 8 amps then gradually settle at 200 mA and after several minutes 40mA. 5 or 20 minutes later the load will hit 3.3 amps for a minute and repeat. Something is waking up.