ESCEE400

Long story short I bought an SC400 with aftermarket alarm already installed but it didn't come with the remotes for it so the guy was just locking and unlocking with the key!

I pulled out the guts under the steering column to try to identify the aftermarket alarm model number and took a gamble to buy another one just so I could get the key fobs. Followed the instructions and reprogrammed the new fobs to the old alarm a VOILA! I couldn't believe it worked...but then I noticed that only the front parking lights pulsed when I armed/disarmed the car. This of course bothered me to no end, especially when I would arm the car from the rear and didn't know if it worked or not since I couldn't see any lights flash!

It took me months of half-*** fiddling and online research to find out what I needed to do. Pics and explanation below

ESCEE400

STEP1: First identify the wire from your alarm that pulses the lights when you arm/disarm. Mine was labeled "lights" (which was a white wire with a in-line fuse) in the manual. I could see the installer ran it and T-tapped into a dark green wire in the drivers kick panel behind the footwell carpet which from the SC400 wiring diagram indicated that it was for the parking lights.

DARK GREEN = PARKING LIGHTS (+)

this should have been all that was required to pulse the parking lights (even the rear ones) but somehow it only controlled the front lights!

STEP2: T-tap into that alarm white wire (parking lights) and run it to the brake lights under the steering column (GREEN/WHITE wire = BRAKE WIRE (+)). To find the right green/white wire you have to crawl under the steering column and follow the brake pedal up to the sensor switch (looks like a push button with a blue port on the back of it, see 2 pics below) and you'll see that it's plugged into a square box that the is plugged into another wire harness. It's this second wire harness that you'll see a green/white wire and that's the one that powers the lights.

White wire sends 12v pulses to flash the lights, tap into that and verify with a volt meter while arming/disarming the alarm.


STEP3: T-tap into that wire and VOILA your rear brake lights should also pulse with your alarm along with the parking lights. The alarm will send the 12v along to the parking lights and since you tapped onto that line and routed it to the brake lights they too will flash!

Run the ALARM (white) wire to the GREEN/WHITE wire under the steering column. You'll need to unplug it from its harness and locate the port it's plugged into.

NB: TEST ALL YOUR CONNECTIONS BEFORE YOU T-TAP. Do not cut into your wires for until you're sure it's the right one and arm/disarming does indeed pulse the rear lights as well as the front ones.

ESCEE400

Looks like this now

ESCEE400

I just took her for a spin and when the engine is on, the brake lights STAY ON. I'm not sure what kind of alarm keeps 12v running through the "lights" wire after the engine is started but I obviously need it off for this to work.

I've unplugged the wire for now and trying to find another way to do this.

SEE UPDATE BELOW: THE POWER WASN'T COMING FROM THE ALARM BUT FROM THE CAR LIGHTS WHEN THE CAR WAS ON!

ESCEE400

OK so I gave up and had to get some relays to make this work. Wired up a 5-pin relay to take the HORN trigger from the alarm to turn on the relay and power the brake lights. Problem is the bursts from the horn output is so quick that the relay doesn’t have time to send the full 12v to the load wire and it ends up only being enough to light up the LED brake lights on the spoiler. Good enough I guess but would have liked all the brake lights to flash instead!


My not so neat wiring


If anyone has any tops on hope you get this to work, I’d appreciate it, thank you!

ESCEE400

This thing kept bothering me so I gave it some more thought and even drew out a crude schematic of the alarm, parking lights, brake lights, fuse, battery and everything else. Trying to make it make sense in my head then it came to me. When I wired it up initially (light flashing from using the alarm light trigger) and then turned on the car the voltage was not coming from the alarm trigger but from the daytime running lights from having the car running. There was nothing preventing the current from flowing back into the brake light as I had connected it to alarm (which was connected to the parking lights) to get them to flash. I just needed a simple diode to only allow current to flow out to the brake light from the alarm and not the car power (when having the car run).

I inserted a diode inline to the brake light to stop the parking lights wire from sending the current upstream back to my brake lights and it worked. An obvious huge sigh of relief from me on the project and I hope this helps someone else.