GM Service Manual Online
For 1990-2009 cars only
Table 1: Vehicle Communication Interface Module Scan Tool Data Parameters
Table 2: Vehicle Communication Interface Module Scan Tool Output Controls

Vehicle Communication Interface Module Scan Tool Data Parameters

Parameter

System State

Expected Value

Definition

Operating Conditions : Ignition ON

Date

--

Numeric

This displays DD/MM/YYYY. This is the date the VCIM was manufactured.

GPS Signal

--

Yes

The scan tool displays Yes or No. Yes is displayed if there is a GPS signal received by the VCIM.

Signal Strength

--

68

The scan tool displays 0-100. This displays a calculated value for cellular reception signal strength. A higher number indicates a stronger signal.

Signal Type

--

Digital

The scan tool displays Digital or Analog. This is the signal type received by the VCIM.

Time

--

Numeric

The scan tool displays HH:MM:SS. This displays the time as synchronized with GPS Satellites.

Transceiver ID

--

Varies

The scan tool displays a 2-5 digit value. This displays the ID number of the cellular tower that the OnStar® VCIM is using for cellular signal.

Vehicle Communication Interface Module Scan Tool Output Controls

Scan Tool Output Control

Description

B1000 Data

This shows the data recorded when DTC B1000 was set in the VCIM.

Green LED

The VCIM illuminates the green LED on the inside rearview mirror when ON is selected.

Phone Call Test

When ON is selected, VCIM commands OnStar to connect to the OnStar Center.

PRL Update

This function performs an update of the Preferred Roamer List. Provides a list of alternate networks to use when the service provider's and/or subscriber's primary wireless network cannot be reached.

Red LED

The VCIM illuminates the red LED on the inside rearview mirror when ON is selected.