How do I hook up the remote entry feature of a remote start unit in a 2004 rendezvous?

Question

I've recently acquired a 2004 Buick Rendezvous, which has an aftermarket remote start unit installed (Excalibur RS-450-EDP+). Unfortunately, the previous owner did not hook up the remote entry feature.

After some initial research, it appeared that a separate unit was required to connect between the remote start and the vehicle. After more research, it appears that maybe a simple resistor is all that's required.

According to the documentation(PDF), the remote start unit wiring looks like this.

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According to this document (PDF), Lock is a negative trigger through a 470 ohm resistor, and unlock is a straight negative trigger.

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Can I simply install a 470 ohm resistor on the Green wire from the remote start unit. Then combine the other end of the resistor, with the Blue wire from the remote start, and the Red/Black wire in the vehicle?

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Or do I have to purchase an additional unit?

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UPDATE:

These Installation Instructions (PDF) seem to agree.

Single Wire (Dual Voltage): Late model Chrysler/Dodge/Plymouth Vehicles, some 2000-UP GM Cars Dual Voltage systems have lock/unlock switches that send varying levels of Positive voltage OR Negative ground current to the SAME wire for both lock and unlock. When the vehicle’s Body Computer Module (BCM) or door lock module senses different voltages on this wire, the system will either lock or unlock. Single wire door lock systems require resistors.

And even provide a diagram similar to the one I've created.

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Answer 1

I assume that at this point you've already figured it out, or gone another route.

Buuut for anybody that's still interested, this will work as described in this photo from above:

The negative outputs (blue and green) are simply connected to ground when the corresponding relay (unlock and lock) inside the remote start is activated. The unit labeled "Factory Door Lock Module" is either looking for a full negative signal, provided by the un-resisted blue wire, or a resistance (470 ohms in this case) from the green wire.

Answer 2

There is that language in Exhibit 2:

Relays must be used

...which indicates to me that you shouldn't tie the two outputs together (even through a resistor), but should use those two outputs to drive a pair of relays which will connect to the car's wiring.

Answer 3

Unless you have a safe and working example to go by, the smart money is to obtain and use the Excalibur's accessory unit. If the installation merely required a 470 ohm resister to extend its functionallity it is a safe bet the manufacturers would have incorporated it already.