GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Generic 🢒 2005 🢒 Unit Repair 🢒 DTC 🢒 DTC B3055

Circuit Description

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the theft deterrent module (TDM). The TDM then compares this value to a value stored in memory, learned key code. If the value is correct, the TDM sends a random generated number to the transponder. This is called a challenge. Both the transponder and the TDM perform a calculation on the challenge. If the calculations match, the TDM sends the fuel enable password via the serial data circuit to the powertrain control module (PCM). If either the transponders unique value or the calculation to the challenge is incorrect, the TDM will send the fuel disable password to the PCM via the serial data circuit.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3055 No Transponder Modulation or No Transponder

This vehicle has DTCs which include DTC Symptoms. For more information on DTC Symptoms, refer to DTC Symptom Description in Vehicle DTC Information.

DTC Symptom

DTC Symptom Descriptor

00

No additional information

Conditions for Running the DTC
    •  The ignition switch is in the ACCESSORY or RUN position.
    • DTC B1325 03 or B1325 07 is not current.
    • DTC U2107 00 is not current.

Conditions for Setting the DTC

The TDM is unable to measure the ignition key transponder value. This may be due to a damaged or missing transponder or a non-Passkey III+ (PK3+) key

Action Taken When the DTC Sets
    • The vehicle will not start.
    • The TDM sends a message via the serial data circuit to the body control module (BCM) to illuminate the SECURITY indicator.

Conditions for Clearing the MIL/DTC
    • The TDM clears the current status of the DTC when it senses a valid, memorized, transponder value from the ignition key.
    • The TDM clears the history status of the DTC after 100 fault-free ignition cycles.
    • The DTC can be cleared by using a scan tool.

Test Description

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

  1. This step verifies the condition for setting DTC B3055 is current.

    2.

  2. The key must be a PK3+ transponder key with an operating transponder for the system to work.

    3.

  3. The only method to confirm whether the transponder in the key or the TDM is malfunctioning is to try an alternative key with the system. The vehicle was delivered with 2 keys.

    4.

  4. The possibility is unlikely that more than one key will be defective. If all keys do not work, the TDM must be malfunctioning.

    5.

  5. If a new key must be tried, the key must have the proper mechanical cut and the TDM must learn the transponder value.

    6.

  6. If only one key was available for the vehicle and the replacement key does not work, the TDM must be malfunctioning.

Step

Action

Yes

No

Schematic Reference: Theft Deterrent System Schematics

Connector End View Reference: Theft Deterrent System Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Is DTC B3055 set as a current code?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

Inspect the vehicle key for damage to the molded head and for + symbol on the key shank.

Is the head of the key damaged or missing the + symbol?

Go to Step 7

Go to Step 4

4

Are more than one of the vehicles keys available?

Go to Step 5

Go to Step 7

5

  1. Attempt to start the vehicle using all of the vehicle available keys.
  2. Using a scan tool, observe for any theft deterrent module (TDM) 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

Important: Two learned master keys are required to perform the Adding Keys procedure on some export vehicles. If only one learned master key is available then the Replacing Keys procedure will need to be performed. Refer to Replacing Keys .

  1. Replace the damaged/inoperative/suspect key.
  2. Perform the Adding Keys procedure. If a learned master key is available, refer to Adding Keys . If a learned master key is not available, refer to Replacing Keys .

Did you complete the replacement?

Go to Step 8

--

8

Does the replacement key cause DTC B3055 to set?

Go to Step 9

Go to Step 10

9

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

    • If original vehicle keys are to be reused, perform the TDM setup prior to TDM replacement. Refer to Programming Theft Deterrent System Components .
    • If new vehicle keys are being used, performing the TDM setup prior to TDM replacement is not required.

Replace the TDM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 10

--

10
  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