GM Service Manual Online
For 1990-2009 cars only

Circuit Description

When an ignition key is inserted into the ignition lock cylinder, the transponder that is embedded in the head of the key is energized by the exciter coils that surround the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the VTD module . The VTD module then compares this value to a value stored in memory (learned key code). If the value is correct, the VTD module sends the enable password via the class 2 serial data circuit to the PCM.

Conditions for Running the DTC

The ignition switch must be in the RUN position.

Conditions for Setting the DTC

The VTD module is unable to measure the ignition key transponder value. This may be due to a damaged or missing transponder pellet, a non Pass Key III® key, or a damaged exciter.

Action Taken When the DTC Sets

  1. The VTD module sends a class 2 message containing a disable password to the PCM.
  2. The vehicle will not start.
  3. The VTD module sends a class 2 message to the instrument cluster to flash the SECURITY message.

Conditions for Clearing the MIL/DTC

The VTD module clears the current status of the DTC when the module senses a key code from the exciter. If the code is not from a learned key, a DTC B2960 will be set.

Test Description

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

  1. Verifies the condition for setting DTC B3055 is current.

  2. The key must be a Pass Key III® transponder key with an operating transponder for the system to work.

  3. The only method to confirm whether the transponder in the key or the VTD (Pass Key III®) module is malfunctioning is to try a alternative component in the system. The vehicle was delivered with 2 keys.

  4. The possibility is unlikely that more than one key will be defective. If all keys do not work, the VTD (Pass Key III®) module must be malfunctioning.

  5. If the vehicle has a malfunctioning VTD (Pass Key III®) module that malfunctioned during an ignition cycle, the system will be "fail enabled" and the vehicle will start for all keys.

  6. If a new key must be tried, the key must have the proper mechanical cut and the VTD (Pass Key III®) module must "learn" the transponder value.

  7. If only one key was available for the vehicle and the replacement key does not work, the VTD (Pass Key III®) module must be malfunctioning.

Step

Action

Yes

No

1

Did you perform A Diagnostic System Check - Theft Deterrent System?

Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2

Is DTC B3055 set as a current code?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

Inspect the vehicle's key for damage to the molded head and for PK3 embossed on the shank.

Is the head of the key damaged or missing the PK3 embossing?

Go to Step 7

Go to Step 4

4

Are more than one of the vehicle's keys available?

Go to Step 5

Go to Step 7

5

  1. Attempt to start the vehicle using all of the vehicle's available keys.
  2. Using a scan tool, observe for any VTD DTCs.

Do any of the available keys start the vehicle?

Go to Step 6

Go to Step 9

6

Do all of the available keys cause DTC B3055 to set?

Go to Step 9

Go to Step 7

7

  1. Replace the damaged/inoperative/suspect key.
  2. Copy the mechanical cut of the available key on a Pass Key III® replacement key.
  3. Perform the VTD module learn procedure. If a learned master key is available Refer to Programming Additional Keys . If a learned master key is not available Refer to Programming Replacement Keys, Ignition Cylinder, or Powertrain Control Module

Is the replacement complete?

Go to Step 8

--

8

Does the replacement key cause DTC B3055 to set?

Go to Step 9

Go to Step 10

9

  1. Replace the VTD module. Refer to PASS-Key III Module Replacement .
  2. Perform the VTD module learn procedure. Refer to Programming Replacement Keys, Ignition Cylinder, or Powertrain Control Module .

Is the replacement complete?

Go to Step 10

--

10

Important: If a 10 Minute or 30 Minute Re-Learn Procedure was performed, all keys not learned at that time have been erased and will not be recognized. Perform the Programming Additional Keys Procedure or instruct the customer on how to perform the Programming Additional Keys Procedure. Refer to Programming Additional Keys .

  1. Use a scan tool in order to clear the DTCs
  2. Attempt to start the vehicle.

Does the DTC reset?

Go to Step 2

System OK