by southpawboston

Most car alarms have a blinking LED to indicate the car has an alarm system and is armed. The '01-'04 Elantra alarm does not have this, and it is not possible to add a true alarm status LED. This DIY adds a dummy LED that flashes whenever the key is off. The LED switches off when the key is in "Acc" or "On" positions.

Materials and tools needed:

·      12V flashing LED. I recommend Varad. They have them in different colors for $5.95 each, including mounting bezels and wiring

·      standard automotive SPDT relay, 30A

·      insulated female spade crimp terminals (4 needed)

·      18-gauge or similar electrical wire, about 2 feet total

·      electrical tape

·      crimp tool

·      electrical tape

·      solder

·      solder gun

·      phillips head screwdriver

·      drill with bits

·      nylon snap ties (recommended)

The Project: 

(Total cost:  $10   Difficulty: easy/med.)

1)   Follow elantraGTclub.com member kmr327's DIY "Easy dash removal". Remove the four screws that secure the HVAC cluster and pull it forward. You do not need to remove the harnesses from the cluster.

2)   Mount the LED anywhere. Drill an appropriately sized hole to mount the LED snug, Common places for an LED include the center dash area, the center console, or in a "dummy" switch bezel (e.g., next to the instrument cluster brightness knob or one of the empty switch plates next to the hazard flasher switch if your Elantra doesn't have a rear wiper or ABS/TCS). I recommend using one of these switch bezels because they are inexpensive to replace if you damage them or drill the wrong size hole, and also because they are close to the clock harness and therefore easy to run the wires.

3)   Wire the LED and relay according to the diagram.  Use insulated female spade crimp terminals to connect the wires to the spades of the relays.

4)   Splice the wires into the corresponding clock harness wires.

5)   After all splice junctions are properly soldered and taped, secure the relay to the dash frame section to the right of and behind the HVAC cluster. There are already two holes which can be used to mount the relay using a self-tapping sheet-metal screw. There is plenty of clearance for the relay to fit.

6)   Secure any loose wiring to existing wiring harnesses with nylon snap ties or electrical tape.

7)   Re-assemble the HVAC cluster and dash fascia.

Project Photos: