Want to cancel Alarm and security key

Simply grounding a factory alarm disarm wire is a for sure way to kill your battery over night. The disarm wire is designed to be pulsed, as if you were turning the key in the door to the unlock position. Grounding that wire just keeps that circuit active, causing a drain that will not go away until it is ungrounded.

Ground the hood pin wire. The SECU will think the hood is open and not allow the factory alarm to arm. You'll retain keyless entry and won't get a drain.

Pretty sure you can just disconnect the SECU but you'll obviously lose keyless entry, power locks, and power trunk pop as stated above.



Easy way to bypass the chip.. yes, hack up a key for the chip and glue it to the transponder ring.

Other way... get a 556U. Put a programmed key inside. Throw the 556U coil around transponder ring. Hook up power, ground, and trigger with the vehicles key sense wire.

Both ways will allow you to start the car with non chipped keys. Just don't try starting the car with another chipped key because the car will see two transponder signals and not start.

Nissans don't constantly monitor the key like say a Mercedes does. Once the car has started and running, it doesn't matter if the RF signal is being seen by the car or not.

But in the way I described, the 556U would be active as long as the key is in the ignition slot. Once the key is turned off and removed, keysense would go away, deactivating the 556U.

There is different ways to wire up a 556U. But basic operation only requires power, ground, and a negative activation trigger. The activation trigger off a remote start system is usually a status output (aka ground while running) off of a remote start brain.

In this case the trigger would be the car's key sense. I can't recall off the top of my head if the G20 is + or - keysense . But if +, a relay would be needed to flip polarity, because the 556U needs a - trigger. I'll look into it when I get a chance.

EDIT: The blue keysense wire off the car is positive, so a relay would be needed to make a negative trigger.

556U's are super easy to wire up BTW. Shouldn't take more than 15 minutes including underdash disassembly/re-assembly.

The 556U manual is confusing if you don't know what you're looking at. For what we are trying to accomplish here, which is getting the car to start without a chipped key, only three wires and the ring are used.

Power (red), ground (black), and status (blue). The pink, green, and purple are not used in this application. You have to remember we are not doing anything remote start here. We just want the bypass to turn on when a non-chipped key is inserted.