GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Garage Door Opener System Check ?

--

Go to Step 2

Garage Door Opener System Check

2

Are the garage door opener (GDO) LED's illuminated?

--

Go to Step 5

Go to Step 3

3

Check the IGN SEN fuse in the IP fuse block.

Is the fuse open?

--

Go to Step 4

Go to Step 5

4

  1. Repair the short to ground on CKT 241 (BRN).
  2. Replace the IGN SEN fuse.

Is the repair complete?

--

Go to Step 16

--

5

Press any button on the GDO.

Does the button LED illuminate?

--

Go to Step 15

Go to Step 10

6

Check the operation of the rear defogger grid (activate the HTD BK LITE relay).

Does the HTD BK LITE relay activate?

--

Go to Step 7

Refer to Rear Window Defogger Inoperative in Stationary Windows

7

  1. Disconnect the GDO connector.
  2. Connect a J 39200 digital multimeter (DMM) from the GDO connector terminal B to ground.

Is the measured voltage within the specified range?

10-15V

Go to Step 8

Go to Step 12

8

Connect a DMM set to ohms scale from GDO connector terminal C to ground.

Is the measured resistance within the specified range?

Less than 5ohms

Go to Step 11

Go to Step 9

9

Repair the open in CKT 650 (BLK).

Is the repair complete?

--

Go to Step 16

--

10

  1. Disconnect the GDO connector.
  2. Connect a DMM from the GDO connector terminal A to ground.

Is the measured voltage within the specified range?

10-15V

Go to Step 11

Go to Step 13

11

Replace the GDO. Refer to Garage Door Opener Replacement

Is repair complete?

--

Go to Step 16

--

12

Repair the open in CKT 241(BRN).

Is the repair complete?

--

Go to Step 16

--

13

Check for proper operation of the vanity mirror lamps and reading lamps.

Do the lamps operate properly?

--

Go to Step 14

Interior Lamps System Check in Lighting Systems

14

Repair the open in CKT 1732.

Is the repair complete?

--

Go to Step 16

--

15

Program the GDO to the customer's transmitter. Refer to Garage Door Opener Programming - Universal .

Is the repair complete?

--

Go to Step 16

--

16

  1. Make sure any components removed during diagnosis are installed in place and that all connectors are connected.
  2. Repeat the system check. Refer to Garage Door Opener System Check .

Is the system check complete?

--

System OK

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