Unable to Contact OnStar Call Center F1
Diagnostic Aids
| • | The customer concern may have been due to a lack of cellular service in a given area. A failure in the National Cellular Network infrastructure at the time of the customer's failed connection that has since been repaired may also have been the cause. |
| • | If an OnStar® Emergency call is able to successfully connect the vehicle to the OnStar® Call Center when an OnStar Call Center button press is not, there may be a failure in the ability of the OnStar® system in the vehicle to be recognized by the local cellular carrier. |
| • | If the prompt "OnStar request ended" is heard without depressing the white "Dot" button at the end of the an OnStar® keypress, the OnStar® system at one time has made a successful cellular connection but was unable to complete the call. If repeated calls are placed with this result, contact the General Motors Technical Assistance Center. |
Step | Action | Value | Yes | No |
|---|---|---|---|---|
Schematic Reference: OnStar Schematics DEFINITION: When the OnStar® Call Center button is pressed, no connection is made to the OnStar® Call Center. | ||||
1 | Did you perform the Cellular Communication Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Important: It is important to have the vehicle in an open outside area where a cellular call can be successfully placed and GPS data can be received from satellites.
Is a connection made with the OnStar® Call Center? | -- | Go to Diagnostic Aids | Go to Step 3 |
3 | Other than the normal progression tones of the system and the prompt "Unable to Contact OnStar®", were any other tones or cellular messages heard? | -- | Go to Step 4 | Go to Step 5 |
4 |
Important: Placing an emergency call to the OnStar® Call Center should only be made if the diagnosis of the system leads to this step. Immediately after an OnStar® advisor picks up the call, they should be told that this call is for diagnostic purposes only and there is no emergency.
Does the emergency keypress call make a connection to the OnStar® Call Center within 10 minutes? | -- | Have all messages heard during the course of the tests available, use the scan tool to access the STID, ESN and Transceiver I.D. and contact the General Motors Technical Assistance Center | Go to Step 5 |
5 | Inspect the Cellular antenna for exterior damage. Is the antenna assembly damaged? | -- | Go to Step 9 | Go to Step 6 |
6 |
Does the meter read out of limits? | -- | Go to Step 7 | Go to Step 8 |
7 | Measure the resistance of the cellular antenna coax center conductor from end to end. Does the resistance measure greater than the specified value? | 1ohms | Go to Step 8 | Use the scan tool to access the STID, ESN and Transceiver I.D. and contact the General Motors Technical Assistance Center |
8 | Replace the Cellular antenna coax. Did you complete the replacement? | -- | Go to Step 10 | -- |
9 | Replace the Cellular antenna assembly. Refer to Mobile Telephone Antenna Inner Coupling Replacement and Mobile Telephone Antenna Outer Coupling Replacement . Did you complete the replacement? | -- | Go to Step 10 | -- |
10 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 |
Unable to Contact OnStar Call Center 2.6
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: OnStar Schematics DEFINITION: When the OnStar® call button is pressed, the audio prompt "Connecting to OnStar®" or "Unable to contact OnStar®" will play and no connection is made. | ||||
1 | Did you perform the Cellular Communication Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Does the green LED flash? | -- | Go to Step 3 | |
3 | Did you connect to the OnStar® Call Center? | -- | Go to Step 23 | Go to Step 4 |
4 | Is a fast busy beep heard? | -- | Go to Step 5 | Go to Step 6 |
5 | Test the operation of the OCC and emergency button. Allow at least 3 minutes for each call to complete. Did you connect to the OnStar® Call Center? | -- | Go to Step 23 | Go to Step 7 |
6 | Are any cellular messages heard? | -- | Record all cellular messages, use the scan tool to access the STID, ESN, and Transceiver I.D. and contact the General Motors Technical Assistance Center | Go to Step 7 |
7 | Inspect for poor connections at the cellular coax connection of the Vehicle Communications Unit (VCU) and cellular antenna base. 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 8 |
8 | Test the cellular coax for high resistance.
Does the resistance measure near the specified value? | Less than 1ohms | Go to Step 9 | Go to Step 10 |
9 | Test for continuity between the cellular coax center conductor and the coax outer metal shield. Is continuity present? | -- | Go to Step 10 | Go to Step 11 |
10 | Replace the cellular coax cable. Did you complete the replacement? | -- | Go to Step 23 | -- |
11 |
Does the voltage measure near the specified value? | 0 V | Go to Step 12 | Go to Step 13 |
12 | Measure the voltage from the OnStar® serial data (-) circuit and a good ground. Does the voltage measure near the specified value? | 5 V | Go to Step 14 | Go to Step 15 |
13 | Test the OnStar® serial data return circuit for an open or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 16 |
14 | Measure the voltage from the OnStar® serial data (-) circuit and the transceiver low reference circuit. Does the voltage measure near the specified value? | 5 V | Go to Step 17 | Go to Step 18 |
15 | Test the OnStar® serial data (-) circuit for an open or short. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 16 |
16 | Inspect for poor connections at the harness connector of the Vehicle Interface Unit (VIU). 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 19 |
17 | Measure the voltage from the OnStar® serial data (+) circuit and a good ground. Does the voltage measure near the specified value? | 5 V | Go to Step 20 | Go to Step 21 |
18 | Test the transceiver low reference circuit for an open or short. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 16 |
19 | Replace the VIU. Refer to OnStar Vehicle Interface Unit Replacement . Did you complete the replacement? | -- | Go to Step 23 | -- |
20 | Inspect for poor connections at the harness connector of the VCU. 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 |
21 | Test the OnStar® serial data (+) circuit for an open or short. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 16 |
22 | Replace the VCU. Refer to OnStar Vehicle Communication Unit Replacement . Did you complete the replacement? | -- | Go to Step 23 | -- |
23 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 |
