<hr><font color=red>Another Good writeup by RedWillow. We truly appreciate your insights.
-G35driver.com TEAM</font color=red>
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I ordered the DEI 504M Stinger Shock Sensor from here:

<a href="http://www.autotechs.com/subcat90.htm">sensor</a>

25 bucks, shipped. Arrived in 2 days.

It detects impacts, shocks and bumps to the car's exterior. I also believe it would detect any of the glass being broken, since it will go off if any of the windows are bumped or impacted in any way.

It is specifically designed to be used with OEM alarms.
The website specs don't show it, but the sensor DOES have a sensitivity adjustment.

It has 4 wires:
RED: 12v power supply
YELLOW: Ground
GREEN: 1st Stage (warning) Output
BLUE: 2nd Stage (full alarm) Output

I installed it using the hood pin switch, located under the hood by the coolant/washer fluid fills.

03 6MT coupe, red/willow, premium, aero, splash guards, alum pedals, clear corners, 15% tint<P ID="edit"><FONT class="small"><EM>Edited by RamboRami on 10/28/03 03:59 PM.</EM></FONT></P>

 

Best I can tell, this switch is used only by the OEM alarm to monitor the opening of the hood and trigger the alarm if it is opened. Basically, I just spliced the Shock Sensor into the hood switch output (LT BLUE/TEAL color) wire, so the OEM Alarm is tricked out to think the hood was opened and sound the alarm, whenever the shock sensor is set off.

Arming and disarming functions are still controlled by the OEM Alarm, so when the alarm is monitoring the hood switch, it will also be monitoring the shock sensor.

I also checked to make sure the OEM Alarm resets itself. According to the owner's manual, for the alarm to shut off, the unlock button must be hit on the fob or the key used. In acutality, if the alarm is set off, the lights flash and the horn sounds for about 45 seconds before it shuts itself off and resets, if the fob or key isn't used to disarm it first.

PARTS I USED:

(1) DEI 504M Stinger Shock Sensor
(2) 1amp 200v Diodes Radio Shack p/n IN4003 (DEI instructions show IN4004 but the IN4003 worked fine)
Several Straight Butt Wire Connectors (blue and red color)
(2) Spade Electrical connectors for 20 (ish) gauge wire with a wide spade
5 Feet (approx) of flex black split automotive electrical conduit
Several Black Plastic Zip Ties
(1) 10" piece of extra 20 (ish) gauge wire


03 6MT coupe, red/willow, premium, aero, splash guards, alum pedals, clear corners, 15% tint

128618-switch.jpg

 

Here is a diagram of how I connected this.
NOTE: I found that using both of the sensor outputs spliced together (blue and green wires) provided more sensitivity, even though the OEM alarm does not have the "first stage" warning type feature supported by the sensor.

WIRING IT IN:

#1. First I connected spade connectors to the ends of the yellow and red wires on the sensor. I also used a butt connector to connect the sensor blue wire & green wire to 1 of the diodes (diode 1 in diagram). NOTE: Diodes have a specific direction. The diode's end with the band on it goes to the end of the green and blue sensor wires. Then, I used another butt connector to connect the second diode (diode 2) and the 10" piece of extra wire (purple in the diagream) to the first diode (diode 1). Note that I was connecting the 2 NON BANDED ENDS of the diodes together with the 10" wire, in this step, as shown in the diagram.

#2. I removed the complete battery compartment cover (which is held on by about 5 plastic clips), put the windows down and disconnected the negative battery cable.

NOTE: During the process of installing and testing the sensor, I ended up disconnecting the negative battery cable several times. When I finally finished, my Bose 6 disc changer DID NOT recognize 4 of my 6 discs. After about 15 minutes of frantically pushing eject and load, I was able to get the discs out and revive it. Needless to say, in the future I will be removing all the discs prior to disconnecting the battery.

I also removed the lead wires to the (2) horns located just behind the grill. I was able to disconnect the leads by reaching through the open area by the hood latch and just pulling the connector off of each horn. Since the lights flash when the alarm goes off, I was still able to test the sensor and alarm without having to listen to the horn.

#3. Next I disconnected the 2 wire plug from the bottom of the hood switch. There was some vinyl covering around the 2 wires going into the plug that I cut off to expose the wires. The TEAL/LT BLUE wire is the output wire, this is where I spliced the sensor in. I cut it about 2 inches down from the connector, creating 2 ends: one 2" long going to the switch and the other going down into another bundle of wires.

#4. Using 2 more butt connectors, I connected the remaining end (end with the band) of diode 2 to the 2" end of the TEAL/LT BLUE wire going to the hood switch. To the other TEAL/LT BLUE wire (going into the bundle of wires) I connected the other end of the 10" piece of wire from #1, as shown in the diagram. Then I reconnected the plug to the hood switch and wrapped the diodes and butt connectors up with electrical tape.

#5. Lastly, I connected the Yellow wire from the sensor to a ground. I used one on the body just under/behind the hood switch, shown in the picture. I also ran the RED wire from the sensor to the positive battery terminal and connected it. Then I reconnected the negative battery cable.


03 6MT coupe, red/willow, premium, aero, splash guards, alum pedals, clear corners, 15% tint

128620-diagram1.jpg

 

MOUNTING THE SENSOR:

I experimented with several different locations to mount the sensor under the hood. Eventually I settled on a small area on the right rear side of the front air duct. There is a small ledge there with 2 holes in it, perfect for mounting the sensor. I used a single zip tie through the hole and around the sensor to fasten it (sensitivity screw facing upward) to the air duct. Then I cut a couple pieces of the conduit to length, crammed all the sensor wires into the conduit and secured it with the zip ties.


03 6MT coupe, red/willow, premium, aero, splash guards, alum pedals, clear corners, 15% tint

128622-battery.jpg

 

TESTING:

I used a 10 lb weight set on top of the hood switch to simulate the hood being closed, while testing. Note that the OEM Alarm system has an approx 20 second arming phase after the keyfob lock button is pressed before the alarm is armed and functional. During this period the Alarm LED is solid red. After it arms, the LED flashes. I tested the sensor by bumping various areas of the car with the system armed to check sensitivity. To adjust the sensitivity on the sensor the small orange screw is turned either clockwise for more sensitivity or counter clockwise for less sensitivity. I have settled on approx 1/3 turn away from fully sensitive with my install method/location.

FINAL NOTES:

It would be better to solder the diode connections and use heat shrink tubing over the connections. I hate soldering so I took the easy way out and used the butt connector/electrical tape method.

The way I have this installed, the sensor itself is on and functioning all the time. However, the OEM alarm will only react to its signal when the alarm is activated. Ideally, the sensor would only be on when the ignition is off or the alarm is armed. Unfortunately, I was not able to find a 12v source for power (under the hood) that is only ON when the ignition is OFF, or a wire that goes to ground ONLY when the ignition is OFF. I checked with some other people who have installed these sensors (on other model cars) in this way and they have told me that the sensor itself being powered all the time has not been a problem in any way.

The purpose of the diodes seems to be to isolate the signals between the sensor and the OEM alarm trigger (the hood switch). Its possible it would work fine without the use of the diodes (didn't try it), but I included them since they are recommended by DEI and only cost 79 cents!

The thought has crossed my mind to install a simple switch on the ground (or 12v power) going to the sensor. This way it could be deactivated any time I want. Maybe something to do the next time I'm bored

There are probably other/better ways to install this, but this is the method that I used. I welcome constructive comments or suggestions.

Bottom line: For around $35 bucks total, I think this is a great little upgrade.

03 6MT coupe, red/willow, premium, aero, splash guards, alum pedals, clear corners, 15% tint

128625-mouted.jpg