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Discussion Starter · #1 ·
I have my Escort Max360 hardwired with a smart cord. I sometimes have trouble seeing or hearing the alert between my exhaust and music. The vibrating module in the seat has to be a simple 12v motor. I’m no electrical engineer but I was thinking of a relay set up. I’m guessing the blue LED in the smart cord box is fed around 3v so I would need a relay to give the seat motor 12v from a 3v trigger. Does such a thing exist? Any ideas or input? Am
I crazy? I’m sure there is constant 12v under the seat for the motors. I am comfortable opening the smart cord box and soldering or whatever else I need to do, although I am hoping to tap into the wire between the box and detector for the trigger voltage for the blue alert light.

Here is the smart cord:
Escort Direct Wire SmartCord (Blue Light) https://a.co/d/0NOkLMu
 

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You've got the right idea. What you suggest, in essence, will work. But. You're right about the LED being low voltage. You may have trouble finding a relay that will operate at that low a voltage, and have the rating for the current your motor will want (not so much the steady-state current. And that has the current required to drive the relay (which it probably won't because LEDs don't draw much current).

The motor won't have much of a load and it won't draw a lot of current once it's running. But at startup, it has to overcome inertia and it'll need Amps to do that). So a tiny low voltage relay may not cut it...

Solid State is the way to go, anyway. You'd want something like this, not a relay: https://www.pololu.com/product/4035

This motor controller has a "PWM" input to control the motor speed. But "PWM" stands for "Pulse Width Modulation" and it goes from a duty cycle of 0% (no pulses, always off) to a duty cycle of 100% (no pulses, always on). So you could drive the PWM pin with the output of the LED and the motor would run at full speed when the LED was on.

Note this has a much higher voltage range than you might think you need for a car's 12V system. I chose that on purpose. Car electrical systems can be very noisy with lots of transients and spikes that go well over 12V. You want some "margin" for your part or it might die a premature death...
 

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It's not a very good write up, but if you can decipher it, it'll show you how to do what you want to do. Instead of driving the LED like in this example (which is basically making your own "smartcord"), you'd drive the PWM input of the motor driver board I linked to, above...
 

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The SSR input voltage min is 3V. Depending on the voltage on the LED circuit, it may not be low enough to reliably trigger the relay without some additional modification. The LED may be fed off a 3.3V regulated supply in the detector, but there's going to be some voltage drop through the cord and the LED will have a series resistor someplace to limit current, which may also drop the voltage (depending on where the signal can be picked up). The board I pointed to will work with input levels as low as 1.8V and ought to work reliably regardless of the LED's operating voltage.

Also, if I can trust the schematic of the smartcord I found on-line, the LED is lit by switching the "low" leg to ground. So the "output" is floating high when it's off. An "inverter" might be required to get the signal to have the right logical state when presented to the relay (or motor controller board).

There's no question that this is doable, but it might require a bit more effort than I was originally thinking. Not a lot more effort. But a bit. How much depending on what you know of electronics... Even though I don't have a V3, though, I'm more than happy to help. I might even be tempted to go bust open my Max360's cord to see exactly what it's doing. I have run in to situations where the stereo is blasting so loud I don't hear the detector's alerts. So adding a vibrating motor to my V2 is an idea with some merit.
 

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Discussion Starter · #10 ·
Thanks for the input guys. I want to tap into the seat vibrator, not install a new one. I could run the trigger wire to the seat and have the relay there to feed 12v to the motor, but in a perfect world I would find the corresponding wire in the lower front dash area. Does anyone know where I could find such schematics?
 

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Discussion Starter · #14 ·
According to a wiring diagram I found in a large FSM online, the BCM communicates with a seat memory control module under the seat thru a serial data connection. So there would be no finding wires near the dash or at the BCM. From there, there are two outputs labeled RR and LR haptic seat motor control. I also found DTCs that mention this haptic motor short to ground AND short to voltage. I am concerned just tapping into one of these wires would throw a short to voltage DTC. With that being said I think I should buy a haptic motor and install it. They are 35-55 bucks online.

Weirdly, this manual claims to be for 14-17 CTS, but also mentions wagon and coupe, so I am a little confused. I have yet to look under my seat but it is pretty tight so I am not sure I will even be able to see anything under the Recaros without removing them. I wanted to at least try to identify these wires and possibly problem then while activating the collision system in the rear.

There are some walk thrus on replacing these in the GM trucks, where the cushion comes up pretty easy without removing the seat. Not sure if its that simple with the recaros. The motors seem to just sit in some void in the foam cushion. I am going to poke around a little bit during the holiday weekend and try to see if I can find any info on removing the seat cover.
 

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At least on the V2, the seats aren't that difficult to get out. Easier on a Coupe because the door is quite a bit wider. It's just 4 bolts and a connector or two. The biggest problem I had was just that the seats were kind of heavy and I have a bad Back. Lifting them out required me to bend in a way my sciatica did not approve of.

Post a link to the schematic you found and I'll take a look. If it's any comfort, I could also be categorized as a EE. :)
 

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Discussion Starter · #16 ·
The link is ok my work computer and it’s over 200mb but this is the screen shot I have with me.
Wood Rectangle Font Office ruler Grille
 

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The manual you have may refer to wagon and coupe because they still made gen 2 cts-v for 2014. I haven't looked under the seat recently but there is a bunch of stuff crammed in there in I remember correctly. Just a word of warning, watch out for the air lines and bags for the seat bolsters if you decide to try and take it apart.
 

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Far as I recollect, Seat Vibration was not an option for any V2 at any time, in which case this page has to be V3 specific.

I agree, it looks like they're switching both sides of the vibration motor and I can't for the life of me understand why they would have done it that way. You're probably better off just grabbing the motor linked to, above, and using that dedicated to the radar detector. It's possible to figure out what the BCM is doing with a Volt Meter, but it's more work than it'd be worth to figure out and then design something that could use the motor independent of the BCM.
 

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Discussion Starter · #20 ·
Far as I recollect, Seat Vibration was not an option for any V2 at any time, in which case this page has to be V3 specific.

I agree, it looks like they're switching both sides of the vibration motor and I can't for the life of me understand why they would have done it that way. You're probably better off just grabbing the motor linked to, above, and using that dedicated to the radar detector. It's possible to figure out what the BCM is doing with a Volt Meter, but it's more work than it'd be worth to figure out and then design something that could use the motor independent of the BCM.
They aren’t switching both sides of the motor, as there are two motors per seat so I think that’s the hot wire for each motor.
 
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