NTG4.5 4.7 Carplay Units - Battery Draining
03-01-2021, 04:55 AM
#1
Junior Member
Thread Starter
NTG4.5 4.7 Carplay Units - Battery Draining
Hi All,
I opened an additional thread as I want to gain some traction on this matter separate to the other thread. My issue is quite unique and I have a feeling this will affect others in the longer term. Someone may be able to shed some light on the matter. I have a carsara unit installed, Most of these units are very very similar.
All of the 48pin harnesses look practically identical and we take the original MOST (Fibre) cables and plug this into the 48pin aftermarket wire which goes into the command. On the most chain we have a few things, The Factory Harmon Kardon Amp, The Media interface (Armrest connection), DAB. I have an aftermarket sound system installed on my vehicle (Harmon kardon disconnected) My system uses the most fibre optics into a DMI (This replaces the most going into my factory HK amp) from there on I send a optical cable into a processor and RCAs into an amp etc. I have had my sound system installed since 2019 and my DMI is powered to the battery as advised, It has its own signal sensing to turn on and off in line with the most connection in. This device sends a remote out to my processor which sends a remote out to my amp (Both are battery powered but we have remotes).
I noticed my aftermarket processor and amp would not turn off after the carplay install. Previously it would operate fine, Taking into account key out of the ignition, Command goes off, The circuitry however still has power for i would say 10-15 mins after all doors are locked. They would however eventually go off after 10 minutes of the vehicle being locked.
I noticed my equipment would just remain on for hours causing a drain after the install of carplay. I decided to do some trouble shooting to work out if my aftermarket sound system equipment had failed but everything operated as intended (I wont list the testing for this as it wont be carplay relevant) I then thought fine i will power the DMI using a fuse in the Sam (Its a very tiny current draw its essentially to just give a remote out and an optical feed, It uses a 3amp fuse) I found the 30amp Harmon kardon fuse (Again my HK amp is disconnected so this is perfect to then use as a switching power source for my DMI), I tested this and thought fine this will be a switched source I will take my accessory power from this to switch on my DMI which will switch on my amps/processors. Oddly this remained constant live.
My command screen goes off as normal there is nothing you can physically tell that makes you think these units leave the command on or anything within the fibre optics loop. However they are installed inline to these components and i have a strong suspicion that for most the drain is minimal when using stock equipment but it is a drain on these components regardless. My situation amplifies the problem as aftermarket equipment draws more power but i believe these units cause a constant drain on the command and the subsequent components on the MOST fibre optic chain.
Can anyone confirm if they understand the workings of these devices and how the 48pin in line cable takes power? Also has anyone managed to workout what the shutdown is on these carplay boxes?
I opened an additional thread as I want to gain some traction on this matter separate to the other thread. My issue is quite unique and I have a feeling this will affect others in the longer term. Someone may be able to shed some light on the matter. I have a carsara unit installed, Most of these units are very very similar.
All of the 48pin harnesses look practically identical and we take the original MOST (Fibre) cables and plug this into the 48pin aftermarket wire which goes into the command. On the most chain we have a few things, The Factory Harmon Kardon Amp, The Media interface (Armrest connection), DAB. I have an aftermarket sound system installed on my vehicle (Harmon kardon disconnected) My system uses the most fibre optics into a DMI (This replaces the most going into my factory HK amp) from there on I send a optical cable into a processor and RCAs into an amp etc. I have had my sound system installed since 2019 and my DMI is powered to the battery as advised, It has its own signal sensing to turn on and off in line with the most connection in. This device sends a remote out to my processor which sends a remote out to my amp (Both are battery powered but we have remotes).
I noticed my aftermarket processor and amp would not turn off after the carplay install. Previously it would operate fine, Taking into account key out of the ignition, Command goes off, The circuitry however still has power for i would say 10-15 mins after all doors are locked. They would however eventually go off after 10 minutes of the vehicle being locked.
I noticed my equipment would just remain on for hours causing a drain after the install of carplay. I decided to do some trouble shooting to work out if my aftermarket sound system equipment had failed but everything operated as intended (I wont list the testing for this as it wont be carplay relevant) I then thought fine i will power the DMI using a fuse in the Sam (Its a very tiny current draw its essentially to just give a remote out and an optical feed, It uses a 3amp fuse) I found the 30amp Harmon kardon fuse (Again my HK amp is disconnected so this is perfect to then use as a switching power source for my DMI), I tested this and thought fine this will be a switched source I will take my accessory power from this to switch on my DMI which will switch on my amps/processors. Oddly this remained constant live.
- I then decided fine let me unplug the carplay box, I ran a fuse tap out from the 30amp Harmon kardon fuse and tested the wire with the boot closed. Low and behold when testing with a meter (Locking doors, Leaving car to power down) the meter showed literally less than 1v e.g 0.083. I tested this quite a few times getting in and out the car, Literally opening a door key not in ignition, I could see it immediately gets power but when you lock the door etc and come back to check it. It turns off after a while as expected.
- Second test - Plug carplay back in retest this exact fuse, Low and behold with carplay back in and locking the car plus doing the same as above, I left this for nearly an hour on a locked car, That 30amp fuse was still constantly showing plus 11volts (It was basically a permanent live)
My command screen goes off as normal there is nothing you can physically tell that makes you think these units leave the command on or anything within the fibre optics loop. However they are installed inline to these components and i have a strong suspicion that for most the drain is minimal when using stock equipment but it is a drain on these components regardless. My situation amplifies the problem as aftermarket equipment draws more power but i believe these units cause a constant drain on the command and the subsequent components on the MOST fibre optic chain.
Can anyone confirm if they understand the workings of these devices and how the 48pin in line cable takes power? Also has anyone managed to workout what the shutdown is on these carplay boxes?
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CaliBenzDriver (02-11-2022)
02-11-2022, 01:59 PM
#3
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MY'14 W212 M276 3.5NA @60kMi
Aftermarket install drains....
Great OP troubleshooting work!
Aftermarket gear causes a drain during power off.
Seems as if the source of your remote power may be keeping your aftermarket gear ON...
Disconnect to simplify:
Try to simplify your circuit to help identify the cause: "sleepless MOST"; "Amp remote"; ...?
If you get all the way back to a basic circuit, then consider these cars are very capable of overnight drain without any aftermarket work. No tinkering necessary to upset SAMS.
Aftermarket gear causes a drain during power off.
Seems as if the source of your remote power may be keeping your aftermarket gear ON...
Disconnect to simplify:
Try to simplify your circuit to help identify the cause: "sleepless MOST"; "Amp remote"; ...?
If you get all the way back to a basic circuit, then consider these cars are very capable of overnight drain without any aftermarket work. No tinkering necessary to upset SAMS.
Last edited by CaliBenzDriver; 02-11-2022 at 08:45 PM.
