Amp turn on/parasitic drain

[airline tech]

I will need to do some (On=Truck) testing to see if my BCM acts the same way, if you are having battery issues and it has a history, I think the AMP install is just highlighting what the BCM has been doing behind the scenes.

Being you mentioned - Dash Cam, unhook it - and see if you get the same voltage behavior.

Also disconnect any - tapped or added power accessories including anything plugged into the outlet in the back seat

Note: This is (Internal BCM) switched power feeds and fuse 35 comes from the (Micro Control) BCM (Ignition - ISP-R) signal - basically it should drop power with key off

I want to also note that Fuse 36 - if you are tapped at the mirror for the dash cam - this is the fuse it is using.

In order to get a clear pic, I had to split the diagram in half

I suspect you have a hidden issue, and something is triggering the BCM to wake back up, it's trying to close the circuit - something triggers it back on - and the BCM is never going into sleep mode - the task is to isolate down where it is coming from.

The best place to start is any and all added accessories.
I will need to do a test with mine to see how it reacts using the same method you did, it's tricky using the BCM sources as a (wake signal) can come from multiple sources and keep the BCM awake - although I did a battery drain test (as a test experiment) i did not have any parasitic draws.

You description of the Amp Turns (On and Off) with the door closed and if you are getting the same results (power wise) even with the AMP disconnected then something else is doing it and the AMP add is just giving you the visual and audable indication of what has been occurring but hidden.
It can be isolated down - with the right procedure for isolation, but I would start with the accessories first - like the dash cam

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[Superspirit]

The dash cam and radar detector are plugged into the front powerpoints. Easy enough to just unplug them. However I'm wondering if the fact I have used forscan to keep powerpoints on for 2hrs after shutdown is what is causing the slow drain. But what I personally find confusing is even when I'm getting the system off to conserve battery the remote start still works fine.

 

[airline tech]

The reason is - different thresholds for th e message vs disable remote start functions (via Ford Pass)

The Power Points - should not cause this type of voltage reaction - it should be a constant draw, however if the dashcam has a (Park Mode) feature I wonder if the cam is shutting off and then turning back on - triggering the voltage (off and back on)

You mentioned (Remote Start) but have a lower trim, is this Ford Pass only or do you have - Start-X? - Either one of the 2 - can be the source of the issue, but more the Start-X as the Ford Pass would be polling the TCU and you would hear the - Waste Gate Actuator (cycling) like it does when you open the driver's door.

I will get some time in the next few days to check mine for confirmation but somethings telling me that the drop to 7 volts and back to 12 - is the BCM shutting down the circuits and then scanning the circuits for confirmation of shutdown - sees activity and powers it right back up and due to this being a Can Bus truck, it could be circuit or bus related.

Basically - when you shut off the truck and then open the door the power should be dropping off the circuits with exception to the -PowerPoints, this is why you will need to open the door and use a screwdriver to close the door latch - if using test tools on the fuses.
Now keep in mind that some modules do stay awake when the truck is off, but it is a small current

This is a normal draw - example - taken at the battery

 

[Superspirit]

The remote start I have is similar to start x but start x doesn't work on my truck. I'm using the fortin evo i posted wiring for it a while back to help with a problem someone else was working on. I know there are several things contributing to this. But I feel if I could find a clean off on switched feed for the amps it would reduce the drain enough to not have to be so concerned about it. Maybe I need to turn the power points off at 5 min instead of 2 hours.

Also the dash camera is a cheapo off Amazon and has no park mode. It simply plugs into power point and comes on when ignition is on. The remote start could be a source to check out but not sure how to go about that without just removing it for a while.

Everyday these problems come up, the more I start thinking time to go get a mid 90's Chevrolet 4x4 and get this FORD out of my life.

After all it had been plauged with one electrical problem after another since day 1.

 

[RangerBill]

The remote start I have is similar to start x but start x doesn't work on my truck. I'm using the fortin evo i posted wiring for it a while back to help with a problem someone else was working on. I know there are several things contributing to this. But I feel if I could find a clean off on switched feed for the amps it would reduce the drain enough to not have to be so concerned about it. Maybe I need to turn the power points off at 5 min instead of 2 hours.

Also the dash camera is a cheapo off Amazon and has no park mode. It simply plugs into power point and comes on when ignition is on. The remote start could be a source to check out but not sure how to go about that without just removing it for a while.

Everyday these problems come up, the more I start thinking time to go get a mid 90's Chevrolet 4x4 and get this FORD out of my life.

After all it had been plauged with one electrical problem after another since day 1.

I would disconnect the power feeds to all your add-ons and check for the parasitic current draw. If it is then normal, <50 milliamps after the truck goes to sleep, hook one item at a time and recheck current draw (or your stray 7 volt reading).

 

[Superspirit]

Also I turned off ford pass 2 years ago. They had new terms that I couldn't agree to so it locked me out and I deleted it. Even the dealer told me the last time it was in, that they couldn't retrieve the code through Ford pass as my truck is not connected. And the code was no longer there. Cleared itself in there parking lot as the light was on when I dropped the truck off.
I'm telling you there is a poltergeist in this truck. It's only the fact I'm a cristian that it hasn't made an all out attack on me

 

[Superspirit]

 

[Superspirit]

Any suggestion on an inexpensive decent quality amp clamp?

 

[RangerBill]

Any suggestion on an inexpensive decent quality amp clamp?

I have the Klein CL390.

https://www.amazon.com/Klein-Tools-...dca2463e6e0e0cf8c3&qid=1773802572&sr=8-4&th=1

 

[Superspirit]

I have the Klein CL390.

https://www.amazon.com/Klein-Tools-CL390-Electronic-Resistance/dp/B08DTDCG7T/ref=sr_1_4?adgrpid=186938350472&dib=eyJ2IjoiMSJ9.g45CAWDeNWR2WHiPtcuSdVOQkZaj8s2tTlYZtc7JVaQ35qWW5UwUXCOu_MRRJVkmeW75_nPnxy5tr_PqHRSYyciLno9WcJ5NKPd_kLVP-ENgsMjE2lUcSsNJO2D5KU2qVvdhOxDr5vOXYhZchyB2ByjKGgHr189rwdDLAwY9OzFrvswyuPwS0d6VYn0zqM0vWRon6Owtcj5HO4YwaQ8c28PBVmkc7IyreFQ7pEFfsjI.5-IAUGIPEyzwqdh3SsE3Op1wETQfccsqoHQzR44Y5BY&dib_tag=se&hvadid=792788056056&hvdev=c&hvexpln=0&hvlocphy=1025001&hvnetw=g&hvocijid=18367704330782060632--&hvqmt=e&hvrand=18367704330782060632&hvtargid=kwd-2298548230297&hydadcr=13146_13767814_2121248&keywords=klein+tools+clamp+meter+cl390&mcid=026e63c8e04c3edca2463e6e0e0cf8c3&qid=1773802572&sr=8-4&th=1

That's actually the one I was looking at. Ordered now.

 

[airline tech]

For a true parasitic draw test, you need a good (Low Amp) Probe that can read low current.
This is what I have and used in my testing
It will read as low as 1 mA - expensive but works great

Ref my chart above for expected (normal) readings - far less than the Klein will show for any true diagnostics

The Klein CL390 will not read any lower than 300mA accurately and will display (0) for anything lower than 200mA

 

[RangerBill]

I have the Klein and have used it for checking for parasitic loads. It will read to 10 milliamps and is a cheaper alternative to the above. It will display below 200ma all the way down to 10ma. Granted, the above would be somewhat more accurate at the lower current readings, but the Klein will work fine for parasitic loads. You don't need to read to the 1ma values to check for a low current drain.

 

[Superspirit]

For a one time use, hopefully the Klein will do the job. Just did an update on the remote start even with it disconnected the sub kept igniting

 

[Superspirit]

Okay still waiting on meter. So I decided to do some other testing. Pulled the remote start and updated it. The entire time it was out and I was programming it in the floorboard with my laptop the sub kept thumping every minute or so. So i pulled the add a fuse and wired the excite to the acm power wire. The amps would not shut off period 30 min later still on. So I tried again to use the gto system in the dsp. I've tried this before and it worked a time or two then quit. We'll it's worked good all day today so going to see if it lasts. The great thing is the amps are off when the truck is off hopefully this fixes the battery drain issue. Will verify with amp clamp when it arrives and update the thread.

 

[Superspirit]

Wanted to add to this thread. I talked to a buddy of mine that owns a shop yesterday. His son was telling me that he had an almost identical problem on a newer challenger. He said he was able to fix it by installing a diode in the amp excite wire. Said the amp was backfeeding the fusebox. So if anymore problems arise. I'll be trying that. It has fixed his challenger.

Also wanted to add, my battery tested at 13.3 static voltage this morning. Now I haven't been checking that in the past but with that voltage I don't think I'll be getting the system off to conserve battery message anymore. Time will tell. Also a test with amp clamp
tomorrow after it arrives this evening. Will be final verification that may someday help others.

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