Sunroof won't close

You mean GMC not Chevy ! Chevy doesn't make the Envoy . There is no way to manually close the sunroof !
Power Sunroof Inoperative
If voltage is not measured on the sunroof switch open signal or sunroof switch close signal circuits, the fault could be in the retained accessory power (RAP) supply voltage circuit, battery positive voltage circuit, or sunroof motor ground circuit. If the sunroof motor is not being powered, neither will the sunroof switch signal circuits.

2

Attempt to operate the sunroof through its full range of functions in order to verify that the power sunroof inoperative fault is present.
Does the power sunroof system operate normally?
--
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
YES - Go to Step 3

3
Is the sunroof in the fully closed position?
--
YES - Go to Step 4
NO - Go to Step 7

4

1. Disconnect the sunroof switch.
2. Turn ON the ignition, with the engine OFF.
3. Connect a 3-amp fused jumper wire to the low reference circuit of the sunroof switch harness connector.
4. Connect the other end of the 3-amp fused jumper wire to the sunroof switch open signal circuit of the sunroof switch harness connector, for 3 seconds.

Did the sunroof open?
--
YES - Go to Step 17
NO - Go to Step 5

5

1. Disconnect the 3-amp fused jumper wire.
2. Measure the voltage from the sunroof switch open signal circuit of the sunroof switch harness connector to the low reference circuit of the sunroof switch harness connector.

Does the voltage measure near the specified value?
B+
YES - Go to Step 13
NO - Go to Step 6

6

Measure the voltage from the sunroof switch open signal circuit of the sunroof switch harness connector to a good ground.
Does the voltage measure near the specified value?
B+
YES - Go to Step 14
NO - Go to Step 10

7

1. Disconnect the sunroof switch.
2. Turn ON the ignition, with the engine OFF.
3. Connect a 3-amp fused jumper wire to the low reference circuit of the sunroof switch harness connector.
4. Connect the other end of the 3-amp fused jumper wire to the sunroof switch close signal circuit of the sunroof switch harness connector, for 3 seconds.

Did the sunroof close?
--
YES - Go to Step 17
NO - Go to Step 8

8

1. Disconnect the 3-amp fused jumper wire.
2. Measure the voltage from the sunroof switch close signal circuit of the sunroof switch harness connector to the low reference circuit of the sunroof switch harness connector.

Does the voltage measure near the specified value?
B+
YES - Go to Step 15
NO - Go to Step 9

9

Measure the voltage from the sunroof switch close signal circuit of the sunroof switch harness connector to a good ground.
Does the voltage measure near the specified value?
B+
Go to Step 14
Go to Step 10

10

1. Disconnect the sunroof motor harness connector.
2. Measure the voltage from the battery positive voltage circuit of the sunroof motor harness connector to a good ground.

Does the voltage measure near the specified value?
B+
Go to Step 11
Go to Step 19

11

Measure the voltage from the retained accessory power (RAP) supply voltage circuit of the sunroof motor harness connector to a good ground.
Does the voltage measure near the specified value?
B+
Go to Step 12
Go to Symptoms - Computer/Integrating Systems in Computer/Integrating Systems

12

1. Turn OFF the ignition.
2. Measure the resistance from the ground circuit of the sunroof motor harness connector to a good ground.

Does the resistance measure less than or equal to the specified value?
5 ohms
Go to Step 16
Go to Step 20

13

Test the sunroof switch close signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 23
Go to Step 18

14

Test the sunroof switch low reference circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 23
Go to Step 18

15

Test the sunroof switch open signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 23
Go to Step 18

16

Test the appropriate sunroof switch signal circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 23
Go to Step 18

17

Inspect for poor connections at the harness connector of the sunroof switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 23
Go to Step 21

18

Inspect for poor connections at the harness connectors of the sunroof motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 23
Go to Step 22

19

Repair the short to ground or open in the sunroof motor battery positive voltage circuit. Refer to Wiring Repairs and Connector Repairs in Wiring Systems.
Did you complete the repair?
--
Go to Step 23
--

20

Repair the open in the sunroof motor ground circuit. Refer to Wiring Repairs and Connector Repairs in Wiring Systems.
Did you complete the repair?
--
Go to Step 23
--

21

Replace the sunroof switch. Refer to Sunroof Switch Replacement .
Did you complete the replacement?
--
Go to Step 23
--

22

Replace the sunroof motor. Refer to Control Module References in Computer/Integrating Systems.
Did you complete the replacement?
--
Go to Step 23
--

23

Operate the system in order to verify the repair.
Did you find and correct the condition?
--
System OK
Go to Step 2

pull down the panel that is directly in front of the sun roof and manually close it.

There should be a crank on your fuse box cover {hexagonal section}. That is the manual closer for sunroof. You have to take off cover for readong/interior light to access the cranking point.

Is the mechanical dirty if so maybe just a good cleaning will do hope this helps

Remove the drive motor and gear assembly from the roof and close the top, then reinstall it.

It can be faulty motor or loose wiring issue or faulty /weak sunroof controlling switch or there is some blockage for sunroof to come down to close or sunroof out of its track the headliner is out of its way.There re many possibilities.All this basics needs to be checked.For further troubleshooting,go through this help link:----
Click the link mentioned below:------
How to Manually Close the Sunroof ? http://howtobyme.blogspot.in/2012/05/how-to-manually-close-sunroof-on-2001.html

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Sunroof Stuck open? http://howtobyme.blogspot.in/2012/05/2001-lexus-is300-sunroof-stuck-open.html

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How to manually close Sunroof on Navigator? http://technoanswers.blogspot.com/2012/01/how-to-manually-close-sunroof-on-2000.html

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This will help.
Thanks.

All kinds of repair manuals are available here.Have a look of this may be you will get something useful.
Cadillac STS 2004 2005 2006 repair manual download

in this case the the chain would need to be replaced

Don't need an owners manual to push the button, to
actuate the sunroof

Maybe you have the owner manual with your
preventative maintenance log book ,where you
write down all you do on the car

If it won't operate correctly, you need a repair shop !!

i think it might be the open and close buttom has something wrong or the motor of the sunroof it is better that it is seen by a specialist