2006 toyota sienna limted

 I think that you are not connecting close enough to the parklites.That is you are  connecting at HL switch control and not directly to parklites.

Hi Wayne3, Thanks for you input but all the connections are made via the ignition harness under the steering column which is also the ideal location of the parking light GREEN/ BLACK (-) wire. This GREEN/ BLACK (-) wire is grounded from the alarm and activates the vehicle parking lights relay. This would be, what I call, the 'BEFORE the relay' wire location. So what you're saying is connect the alarm park light output wire directly to the park lights preferably running the wire into the engine compartment. This would be, what I call, the 'AFTER the relay' wire location. Am I understanding you? However, I'd like to throw this out there that the park lights DO work when the HL switch is NOT in the automatic switch position and the GREEN/ BLACK (-) wire is where the alarm output is connected which pretty much what all wiring diagrams indicate to do. Can anyone else gather any thoughts as why the automatic headlight switch disables the GREEN/ BLACK (-) wire Somehow I'm thinking this has to do with the sensor in general and overrides the GREEN/ BLACK (-) wire at the ignition harness. Why??? I don't know. Could be a factory Toyota thing.... I wonder if this only happens on Siennas and not other Toyota vehicles with auto HL feature... Anyone care to test and find out???

Ok an update: Worked on this a few hours yesterday and determined there was no choice but to connect to the hazard light wire to see the lock/unlock alarm flashes when set to auto-HL. The 'After the relay' PL output wire I tested came out to be moot. That wire is grounded at all times. Seems it switches from ground to 12v when the PL relay gets the (-) signal from the HL switch or (-) pulse from the alarm. After testing the hazard wire, I figured the (-) 1 sec momentary PL lock/unlock pulse from the alarm is good enough because if the pulse was any longer than that, the hazard lights will flash 2x from a 1x pulse. That would suck. Well at the end, I decided to connect the alarm PL output wire to both the hazard and PL wire on this car. Diodes are used to isolate the hazard and PL circuits. I did this for the remote start PL flashes as well. Wiring it this way worked out better than expected. The PL wire from the alarm has a steady 2sec 12v output between pulses so the car parking lights just stays lit for the 2sec duration while the hazards flashes 3x, ten pauses and then starts the cycle again. Really looks cool and different. By just looking at the flash scheme, you definitely will know the car is remote started. Of course, since the PL lights don't work when set to auto-HL, the hazard pulse timing is synchronized with the alarm lock/unlock pulse. So, this ends my Sunday morning write-up...