GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The Pass-Key® III Theft Deterrent (VTD) Module performs internal tests on the EEPROM each time that the VTD module performs a write function to a memory address in the EEPROM. The VTD module reads back the data that has been written and compares it to the data. If the data does not match after 3 consecutive write and verify attempts, the VTD module will indicate a write malfunction is current.

Conditions for Setting the DTC

    • The data read back after a write does not match the data being written 3 consecutive times.
    • The VTD module detects an internal write malfunction.
    • The condition must occur when data is being written.

Action Taken When the DTC Sets

    • Stores a DTC B1007 in the VTD module memory.
    • No driver warning message will be displayed for this DTC.
    • The VTD module will store the value being written in another memory address in the EEPROM.

Conditions for Clearing the DTC

    • This DTC requires a successful write in order to change from current to history.
    • The VTD module no longer detects an internal write malfunction.
    • A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • Use the On-Board clearing DTC feature.
    • Use a scan tool.

Diagnostic Aids

Since the EEPROM cannot be removed from the VTD module and DTC B1007 is an internal VTD module malfunction the VTD module may be replaced. Refer to diagnostic table.

Test Description

The numbers below refer to the step numbers on the diagnostic table:

  1. Perform the Theft Deterrent System Diagnostic System Check before continuing with the diagnosis of this DTC.

  2. Clear all DTCs and cycle ignition to check that the DTC did not falsely set.

  3. Clear all DTCs after the repair procedure is complete.

DTC B1007 EEPROM Write Error

Step

Action

Value(s)

Yes

No

1

Was the Theft Deterrent System Diagnostic System Check performed?

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Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2

  1. Turn ON the ignition.
  2. Clear any DTCs. Refer to Clearing DTCs .
  3. Turn OFF the ignition.
  4. Turn ON the ignition.

Is the DTC still present?

--

Go to Step 3

Go to Diagnostic System Check - Theft Deterrent

3

Replace the VTD Module. Refer to Theft Deterrent Module Replacement .

Refer to PASSLOCK Reprogramming Auto Learn .

Is the replacement complete?

--

Go to Step 4

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4

  1. Turn OFF the ignition.
  2. Reconnect or install any connectors or components that were disconnected or removed.
  3. Turn ON the ignition.
  4. Clear any DTCs. Refer to Clearing DTCs .

Are all DTCs cleared?

--

Go to Diagnostic System Check - Theft Deterrent

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