NAV-SYS900DVD in Trailblazer

I am about to install a Pioneer NAV-SYS900DVD Navigation System in a 2002 Chevy Trailblazer. I have the wiring diagrams for this SUV and I have already installed a faily complex remote starter/Alarm in it. But I do have a few questions on this installation.

1. Where can I locate the Vehicle Speed Pulse (VSS?) (Pink Wire)

2. Where can I locate the Parking Brake detection (Light green wire)

3. I have been told that if the factory radio is removed from this vehicle, a lot of functions will stop working. Like the airbags, Idiot lights, etc. Why is this? I was told that I need to keep the factory radio installed. When I can install this radio? And where can I get a harness to connect it.

Thanks for all help with this.

1. Where can I locate the Vehicle Speed Pulse (VSS?) (Pink Wire)

•  SPEED SENSE---------------GREEN / WHITE---------------blue plug, pin 32 @ PCM ( The PCM (Powertrain Control Module) is on the driver side of the motor )

2. Where can I locate the Parking Brake detection (Light green wire)

• find the E-brake and it will be the wire attached to the connecting arm of the hand brake.

3. I have been told that if the factory radio is removed from this vehicle, a lot of functions will stop working. Like the airbags, Idiot lights, etc. Why is this? I was told that I need to keep the factory radio installed. When I can install this radio? And where can I get a harness to connect it.

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