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As they say anything is possible. But it would require some type of sensors that the car is not in any gear and the park brake is set. There could be other requirement for the to work. Like are doors locked, amount of fuel in tank, possible distance from remote and car and maybe a few items.
 

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Done it before

Most reliable way in my opinion, is to route the clutch sensor through the shifter via reed switch. I’ll explain.

Your car starter motor won’t work because it is interlocked to the clutch. You can ground out the clutch and the remote start will work normal. But that’s a bad idea IMO because you have to remember to keep the car in neutral, and also you can start the car in gear with the key too. It’s just a bad idea all around.

So what you can do is ground out the clutch through a reed switch that is active only when the car is in neutral. You do that by installing the reed switch in the center console next to the shift lever, and epoxying the magnet to the rod of the shifter. Tune it until the switch is met in neutral, but not in first or reverse.

For the wiring, you ground one end of the wire locally, then route the other wire to the clutch sensor and tap it in to the right wire.

The net result is that the car doesn’t know the difference between a depressed clutch, or the car in neutral. Either case, the car will start. Key or remote.

More importantly, when the car is in gear, then the clutch sensor will prevent the car starting, key or remote.

There are other ways to do it I am sure, but none as elegant, simple, and safe as this way. If there is, I haven’t heard of it yet...
 

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If you want to sense the e-brake too, no problem. Instead of grounding out the reed switch that is connected to the clutch, connect it to your e-brake. Thus, ground will not be supplied unless the e-brake is set.

That way, you need to be in neutral AND with ebrake set to bypass the clutch. Otherwise, the clutch sensor will disallow crank, key or remote start.
 

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I think it is more possible to an automatic gearbox. But I'm also expecting to see that you said to come into reality years later.
 

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No really, none of this years later stuff. Do what I said in the post above, and you have a safe remote start in a manual transmission that won’t drive your car off while you aren’t in it.

If anyone insists on an appeal to authority, I worked in an audio shop installing (among other things) car alarms and remote starts. I have tons of experience wiring up any and every kind of alarm module (pre smart phone) into a car, and even invented one or two of my own. Including the reed switch concept above. It works.
 

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Done it before

Most reliable way in my opinion, is to route the clutch sensor through the shifter via reed switch. I’ll explain.

Your car starter motor won’t work because it is interlocked to the clutch. You can ground out the clutch and the remote start will work normal. But that’s a bad idea IMO because you have to remember to keep the car in neutral, and also you can start the car in gear with the key too. It’s just a bad idea all around.

So what you can do is ground out the clutch through a reed switch that is active only when the car is in neutral. You do that by installing the reed switch in the center console next to the shift lever, and epoxying the magnet to the rod of the shifter. Tune it until the switch is met in neutral, but not in first or reverse.

For the wiring, you ground one end of the wire locally, then route the other wire to the clutch sensor and tap it in to the right wire.

The net result is that the car doesn’t know the difference between a depressed clutch, or the car in neutral. Either case, the car will start. Key or remote.

More importantly, when the car is in gear, then the clutch sensor will prevent the car starting, key or remote.

There are other ways to do it I am sure, but none as elegant, simple, and safe as this way. If there is, I haven’t heard of it yet...
^^^^^
This is a super smooth end result for sure. It takes a little more elbow grease than a "plug-n-play" factory solution, but it also functions much more usefully in the real world. This is definitely the way I would go if I never needed it again!

My last manual gearbox car had remote start that was installed by a local installer, and they followed all the instructions without variation. It was a standard solution that was "safe", but resulted in a remote start that was barely more effective than the Mercedes Me remote start.

There were several conditions that had to be met to "enable" the system, (Had to exit the vehicle with it running, in neutral, parking brake on, etc. and do it in an exact order of operations.) and pretty much anything you did would disable the system. The biggest hassle was, when the system is enabled, and you open ANY door on the vehicle, the system was cancelled. For example, you forget something in the car and go back to retrieve it. You've just cancelled the remote start ability unless you get back in and repeat the entire enabling sequence. You also had to exit the vehicle with it running in neutral, which was weird because you turn off the key and remove it but the car keeps running until you exit and shut the door. People unfamiliar with this (which would be pretty much everyone) were very panicked that the car did not shut off (if I forgot to tell them about it).

I ended up cutting all those door switches so that only the driver's door would cancel the system. It created a potentially unsafe condition, but it was a risk I was willing to accept just to make the remote start useful. It made a world of difference for me, and nothing bad ever resulted from that unsafe modification.

If you could find an installer with the mad skillz that Whiterabbitt has described, you'll be MUCH more happy. I wish I had that knowledge when I needed it!

Thanks for sharing Whiterabbitt!!!
 
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