Adding a remote start to a factory keyless entry

My customer is kinda set on keeping his factory system, but I sure as hell am not going to mess with the factory system if it is that buried.  I am just going to have to talk him into upgrading the whole system.

What do you mean that the keyless entry is only two extra wires?

Is the trunk release negative trigger?  How about the locks?

Lock and unlock are negative trigger, in either kick panel......there is only one important thing to remember:  Don't use the wires that test by operating the lock unlock switch on the door-----they won't arm/disarm the factory alarm, and the unlock function of the switch becomes disabled if you lock the door and then close it---go ahead and try for yourself.

Lock is negative trigger, blue/white, in either kick panel---- you test this wire by inserting the key into the door and twisting it to the lock position.  This wire will also arm the factory alarm.

All doors-unlock is blue / YELLOW in the passenger kick, it tests by twisting the key in the passenger door, and it will also disarm the alarm.

Two-step driver's priority unocking is in the driver's kick, but I forget the color.  Again, you test this wire by twisitng the key in the door, and it will disarm the factory alarm too.

To disarm the factory alarm during remote start, you'll also need to "trick" the car into thinking there's a key in the ignition.  The key-sense wire is at the key cylinder, and it tests as negative whenever a key is inserted.  I think the color is red with some kind of stripe.  Anyway, use an output from your remote starter that puts out a ground the whole time the remote start is on.

Trunk release is GREEN / WHITE, in the driver's kick panel, and it will show a ground whenever you turn the key in the trunk cylinder.  There are several GREEN / WHITEs in there, so you'll have to test each one until you find it, but it's going to be one of the smaller ones.  It is a simple negative trigger; no relays required.  This wire will also disarm the factory alarm.