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Is remote started car running?

Thread starter #1
My garage is 70' from house and car has remote starter. Occasionally in cold weather it falters on start with remote starter and I have no way of knowing till I come to a cold car.

I tried a couple of cheap Chinese sound detector modules but they are not sensitive enough between on and off adjustment. I now have a LDR (detecting head lights) controlling a LED (pointed at house through siding) through a FET but when the car fails to start the lights do still come on.

Looking for ideas on how to detect if car is running other than lights. ARN'T I LAZY?

Aaron
 

dknguyen

Well-Known Member
Most Helpful Member
#2
You could detect the engine temperature, I guess. Or perhaps, the rate of change of engine temperature might be more useful. Or engine vibration.

Or a two-way car starter.
 

dknguyen

Well-Known Member
Most Helpful Member
#4
- Manifold vacuum
- Tach signal
- Alternator output
Is alternator output reliable if the battery is fully charged? Or are you talking about measuring current going to something other than the battery?

And is it difficult to hook into the tach on a car? I thought that was one of the bettery ways but it seemed invasive.
 

BobW

Active Member
#5
The system voltage should rise slightly, even if the battery is fully charged. IIRC, this is a preferred method of detecting engine running status if there's no tach signal available.
Yet another option is detecting oil pressure. But, these methods are all invasive to some extent. If the intention is not to make any connections to the vehicle at all, then I don't think I have an answer.
 

Mickster

Well-Known Member
#7
A non-invasive method?
If it ain't running, there ain't flow through the exhaust.
How about a paddle-wheel directly behind the tail-pipe, on a supported shaft, with a slotted disc triggering a photo-interrupter on the other end?
To reduce/prevent false-triggering from the wind, as I assume that the garage door will be open to ensure no fume build-up, enclose the paddle-wheel in a duct.
It would mean putting the contraption behind the tail-pipe each night, but surely you are not that lazy? :D

Regards.
 

crutschow

Well-Known Member
Most Helpful Member
#8
I think you should look further at a sound detection device since it involves no connection or contact to the car.
Perhaps with a little filtering we can make them work.

What devices do you have?
How did you wire them to give the signal?
What is the car and engine type?
 

dknguyen

Well-Known Member
Most Helpful Member
#9
I think you should look further at a sound detection device since it involves no connection or contact to the car.
Perhaps with a little filtering we can make them work.

What devices do you have?
How did you wire them to give the signal?
What is the car and engine type?
Contact micrphone like those used to tune musical instruments in a noisy environment? If it's not sensitive enough to detect the engine idling, it should be sensitive enough to detect the initial jolt of an engine turnover if it's placed in the right area of the cabin...like maybe the windshield?
 

Reloadron

Well-Known Member
Most Helpful Member
#10
During Fall last year we finally finished the new garage build and I finally have power out there. For Christmas my sister bought us a pretty cool intercom which works great. I can sit in the kitchen and hear a pin drop in the garage, I can certainly hear my or my wife's truck running. Simple and effective. Heck if I open the door I can even see the exhaust in the cold. This Summer we plan to insulate and heat the building. I have the natural gas line run, just need inside walls and a small gas fired furnace. I would just look for an inexpensive audio system with good sound pickup.

Ron
 

MikeMl

Well-Known Member
Most Helpful Member
#11
How about a carbon monoxide alarm in the garage :banghead:
 

dr pepper

Well-Known Member
Most Helpful Member
#12
Excepet in a few cases battery voltage will rise to 14v fairly quickly even with a low battery, a voltage comparator is an option, here in the Uk dim dip back in the 90's used to use something like this.
Engine tacho is a very reliable method.
Because there is an element of ripple in the alty output you might be able to use a current transformer on the alty lead and detect the ripple generating an engine run output.
And then you could go really Ott and use the vehicles Obd port.
 
Thread starter #15
Thanks. A few things have struck me as being possibilities.

It's true that I want a non invasive (no hook up)

and no preparation way of doing this. The car is mainly used by my wife. At some times of the year prestarting is only occasionally necessary.

What devices do you have? >>
https://www.amazon.com/gp/product/B00TM7R21W/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
https://www.ebay.com/itm/MIC-1000-M...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

How did you wire them to give the signal? >> LED stuck through hole in siding, pointed at house
What is the car and engine type? >> Toyota Camry


I do think sound is the best way to do this. I'm not opposed to builing a simplish device.

Aaron
 

kubeek

Well-Known Member
#16
doesn't the car have the usual inidcator lights on the dashboard for low oil pressure and no charging? I would detect one of those.
 

crutschow

Well-Known Member
Most Helpful Member
#19
I do think sound is the best way to do this. I'm not opposed to building a simplish device.
So what circuit/connection did you use at the output of the sound detectors you have?
It would seem that with a little added circuitry, such as a rectifier and comparator, one of those should work for you.
 
Thread starter #20
So what circuit/connection did you use at the output of the sound detectors you have?
It would seem that with a little added circuitry, such as a rectifier and comparator, one of those should work for you.
Just a LED and resistor on the digital output. That part worked fine but setting the threshold was the problem. Too much hysteresis between on and off.
 

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