GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Catera 🢒 Body and Accessories 🢒 Data Link Communications 🢒 Scan Tool Does Not Communicate with Sunroof Actuator

Step

Action

Value(s)

Yes

No

1

Was the Data Link Communications Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - Data Link Communications

2

Attempt to establish communication with the theft deterrent module (immobilizer).

Does the scan tool communicate with the immobilizer?

--

Go to Step 3

Go to Step 4

3
  1. Disconnect the sun roof actuator connector.
  2. Measure the resistance between the connector terminal 4 and the data link connector (DLC) terminal 3. Refer to Testing for Continuity in Wiring Systems.

Does the resistance measure less than the specified value?

.5 ohms

Go to Step 5

Go to Step 6

4
  1. Turn OFF the ignition.
  2. Disconnect the scan tool from the DLC.
  3. Inspect for poor connections/terminal tension at the DLC terminal 3. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

Did you find and correct a poor connection condition?

--

Go to Step 7

Go to Step 8

5

Inspect for poor connections at the sun roof actuator connector terminal 4. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

Did you find and correct a poor connection condition?

--

Go to Step 7

Go to Step 9

6

Locate and repair an open in the sun roof actuator serial data circuit.

Is the repair complete?

--

Go to Step 7

--

7

Attempt to establish communications with the sun roof actuator.

Does the scan tool communicate with the sun roof actuator?

--

System OK

--

8
  1. Disconnect the immobilizer connector.
  2. Attempt to communicate with the sun roof actuator.

Does the scan tool communicate with the sun roof actuator?

--

Go to Step 10

Go to Step 11

9
  1. Inspect the SUNROOF fuse for an open.
  2. Inspect and test the sun roof actuator battery feed circuit at terminal 1 for proper voltage (11-13 V).
  3. Inspect and test the ground circuit at terminal 2.
  4. Make necessary repairs.

Did you find and correct any conditions?

--

Go to Step 7

Go to Step 12

10

Replace the immobilizer.

Is the replacement complete?

--

Go to Step 7

--

11
  1. Disconnect each module on the serial data circuit (DLC terminal 3).
  2. Test the serial data circuit, of the DLC, for a short to ground. Refer to Testing for Short to Ground In Wiring Systems.
  3. Test between terminal 3 and the following terminals at each module.
    4. • Immobilizer connector terminal 8
    • Sun Roof Actuator terminal 4

Did you find a short to ground in the serial data circuit?

--

Go to Step 13

Go to Step 14

12

Replace the sun roof actuator.

Is the replacement complete?

--

Go to Step 7

--

13

Locate and repair the short to ground in the serial data circuit.

Is the repair complete?

--

Go to Step 7

--

14

Test the serial data circuit, of the DLC, for a short to voltage between terminal 3 and each module. (Turn ON the ignition, leaving the engine OFF, when testing for a short to voltage.)

    • Immobilizer connector terminal 8
    • Sun Roof Actuator connector terminal 4

Did you find a short to voltage in the serial data circuit?

--

Go to Step 15

Go to Step 16

15

Locate and repair the short to voltage in the serial data circuit.

Is the repair complete?

--

Go to Step 7

Go to Step 8

16
  1. Reconnect all disconnected modules.
  2. Reconnect any other disconnected connectors.
  3. Install the scan tool.
  4. Turn ON the ignition, leaving the engine OFF.
  5. Attempt to establish communications with the sun roof actuator.

Does the scan tool communicate with the sun roof actuator?

--

Go to Step 17

Go to Step 12

17

It is apparent that the module communication condition is intermittent. Refer to the following:

    •  Intermittents and Poor Connections Diagnosis in Wiring Systems
    •  Testing for Electrical Intermittents in Wiring Systems

Did you find and correct the condition?

--

Go to Step 7

--