2007 gmc envoy

Try stepping on the brake when trying to shift with the key on. Then try starting im neutral or other gears to see if the neutral safety switch is bad in park. You may have a bad wire from the battery to power distrubution or bad ground. So many things it could be.

Try cranking with shift lever in neutral in case the park neutral safety switch is going bad .

• Neutral safety switch sends a signal to the on-board computer to allow the engine to start and to engage the transmission
• When not replaced, vehicle may experience no start and/or transmission will not shift out of park.Here's a link to the part,

Duralast Neutral Safety Switch DR4146 Read Reviews on Duralast DR4146

The brake lamp switch is located on the brake pedal assembly under the dash. (See Diagram)

To move the vehicle, try this:

1. Turn the key to OFF.
2. Apply and hold the brake until the end of Step 4.
3. Shift the transmission to NEUTRAL (N).
4. Start the vehicle and then shift to the drive gear
you want

If it's a no crank condition, put your foot on the brake, shirt the gear selector to neutral and see if the engine will start. If it starts in neutral, you might have a faulty neutral safety switch which is located on the transmission. Very easy to change, but don't remove the steel alignment tool until you have it bolted to the transmission, Good luck, Gary

Yes it has a shift cable.

Yes it can, just place your Transfer Case in Neutral position.
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:

Make sure the vehicle is parked so that it will not roll.
Set the parking brake.
Start the vehicle or turn the ignition to RUN.
Connect the vehicle to the towing vehicle.
Put the transmission in NEUTRAL (N).
Shift the transfer case to 2HI.
Simultaneously press and hold the 2HI and 4LO buttons for 10 seconds. The red NEUTRAL light will come on when the transfer case shift to NEUTRAL is complete.
Shift the transmission to REVERSE (R) for one second, then shift the transmission to DRIVE (D) for one second, or FIRST (1) for vehicles equipped with a manual transmission.
Turn the ignition to LOCK.
Place the transmission shift lever in PARK (P), or FIRST (1) for vehicles with a manual transmission.
Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:

Set the parking brake and apply the regular brake pedal.
Shift the transmission to NEUTRAL (N) and turn the ignition to RUN with the engine off.
Press the button for the desired transfer case shift position (2HI, 4HI, AUTO 4WD or 4LO).
After the transfer case has shifted out of NEUTRAL the red light will go out.
Release the parking brake.
You may start the engine and shift the transmission to the desired position.
Excessively shifting the transfer case into or out of the different modes may cause the transfer case to enter the shift protection mode. This will protect the transfer case from possible damage and will only allow the transfer case to respond to one shift per 10 seconds. The transfer case may stay in this mode for up to three minutes.
NEUTRAL: Shift the vehicle's transfer case to NEUTRAL only when towing your vehicle.
Good luck and hope this answers your question.

Shifting to NEUTRAL
To shift the transfer case to NEUTRAL, first make sure
the vehicle is parked so that it will not roll:
1. Set the parking brake.
2. Start the vehicle.
3. Connect the vehicle to the towing vehicle.
4. Put the transmission in NEUTRAL (N) or have
the clutch pedal pressed for vehicles with
manual transmission.
5. Shift the transfer case to 2HI.
6. Simultaneously press and hold the 2HI and
4LO buttons for 10 seconds. The red NEUTRAL
light will come on when the transfer case shift to
NEUTRAL is complete.
7. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second or FIRST (1) for vehicles with
manual transmission.
8. Turn the ignition to OFF.
9. Place the transmission shift lever in PARK (P) or
FIRST (1) for vehicles with manual transmission.
10. Release the parking brake prior to towing.

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Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular
brake pedal.
2. Start the vehicle with the transmission in PARK (P)
or FIRST (1) for vehicles with manual transmission.
3. Press the button for the desired transfer case position
(2HI, 4HI, AUTO 4WD or 4LO).
4. Put the transmission in NEUTRAL (N) or press the
clutch pedal for vehicles with manual transmission.
5. Shift the transmission lever to the desired position.
After the transfer case has shifted out of NEUTRAL,
the red light will go out.
6. A re-engagement sound is normal when shifting out
of NEUTRAL.

If the gearshift indicator says it is in neutral and the vehicle rolls like it is in neutral, and it starts like it is in neutral...it is probably stuck in neutral, not park. Block the wheels and set the parking brake so the vehicle cannot roll over you then crawl under the driver's side and check the shift cable where it attaches to the lever on the side of the transmission. I have seen a few of these come loose due to wear in the shift cable end. You can usually snap it back on there and it will work again for a while, but it will come back off again. You can get a new cable from the dealer. If they have to order it for you, the cable might stay on for a few days while you are waiting for your new cable to arrive.

I also have a 2002 Envoy. Shifting to and from 4wh and 4wa can be done on the fly but shifting to 4wL has to be done stoped and while in neutral. Try that. Otherwise I'm afraid its a new computer for you. Its located under the left rear seat and you need a loan for one.