DTC B3055
Diagnostic Instructions
DTC Descriptor
DTC B3055 00: No Transponder Modulation or No Transponder
Circuit/System 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 energised by the exciter coils surrounding the ignition lock cylinder. The energised 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. This stored value is the learned key code. If the value is correct, the TDM will send the pre-release password via the serial data circuit to the engine control module (ECM). If the learned key code does not match or a transponder value is not received, the TDM will send the start disable password to the ECM.
Conditions for Running the DTC
Ignition is in the Accessory or Run position.
Conditions for Setting the DTC
The TDM is unable to measure the ignition key transponder value.
Action Taken When the DTC Sets
| • | Vehicle starting will be disabled. |
| • | The security indicator will be illuminated. |
Conditions for Clearing the DTC
| • | A current DTC will be cleared when the TDM detects a valid transponder value from the ignition key. |
| • | A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs. |
Diagnostic Aids
In some instances, RF devices attached to a key chain or otherwise in close proximity of the ignition cylinder may cause interference in the immobiliser system and lead to a no-start condition. Some common RF devices that may be attached to a key chain are Speedpass petrol station payment device, swipe devices used to gain access to locked gates or 24-hour gyms, or other "smart" keys.
These RF devices interfere with the communication between the transponder located in the key and the TDM. The immobiliser systems operates at a frequency of 125 kHz. RF devices that operate in the 120 to 135 kHz range, or a multiplier of these frequencies, are most likely to cause interference. If interference occurs, DTC B3055, B3060, or B3935 may be set.
If interference is suspected, removed the suspect device from the key chain and attempt to start the vehicle. If vehicle starting occurs with the device removed, instruct the customer to remove the device from the key chain to prevent further occurrences. It may also be necessary to inspect all of the customers key chains if the concern is intermittent and doesn't occur with every key.
Reference Information
Schematic Reference
Immobiliser Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Immobiliser Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Important:
| • | When using this diagnostic, more than one vehicle key is required to ensure proper diagnosis. If more than one key is not available at the time of service, contact the customer and ask if any other keys can be provided for service. If unavailable, a new second key can be created. |
| • | Interference from an RF device located on the key chain may cause this DTC to set. Remove any RF devices from the key chain before proceeding with the diagnostic. |
- Inspect all available vehicle keys that they are correct vehicle keys.
| ⇒ | If not a correct vehicle key, replace the key. |
- While viewing the scan tool Invalid Key parameter, turn ON the ignition with each of the available vehicle keys. The parameter should read No with all available keys.
| ⇒ | If only one key results in the parameter reading No, replace the appropriate key. |
| ⇒ | If all available keys result in the parameter reading No, replace the TDM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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