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DTC 1

DTC 1 UNTAUGHT TRANSPONDER

Component Location:






GENERAL DESCRIPTION
During the key teaching procedure the transponder will be programmed with vehicle specific data. The vehicle specific data are written into the transponder memory. The write procedure is unique; therefore the content of transponder can never be modified or changed.

The data are a string of 9 bytes defined by vehicle manufacturer. The transponder memory is split into two strings called authenticator and key password After this programming the transponder memory is locked and the data (PIN code) cannot be read or changed respectively.

The transponder status changes from "virgin" to "learnt". Additionally every transponder includes a unique IDE (Identifier number) of 32 bit. Unique means that the IDE of all transponder is different from each other. The IDE is programmed by the transponder manufacturer and is a read-only value. The authenticator and the key password are not transferred from ECM to transponder or vice versa. Only the results from the encryption algorithm are transferred. It is almost impossible to calculate the vehicle specific data from the encryption result. For teaching of keys and special purposes the ECM is connected to the tester device.

When IG is ON, the coil supplies energy to the transponder which in turn accumulates energy in the condenser. Once the energy supply from the coil has stopped, using the stored energy in the condenser, the transponder transmits the ID CODE (stored within the ASIC).

DTC DESCRIPTION
This DTC indicates that Transponder is not taught yet.

DTC Detecting Condition:






Schematic Diagram:











MONITOR SCANTOOL DATA
1. Ignition "ON" & Engine "OFF".




2. Connect Scan tool and monitor "CURRENT DATA".
3. Is key status display Number of the current transponder key?

YES
- Fault is intermittent caused by poor contact in the BCM and/or the antenna coil connector or was repaired and BCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
- Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

NO
- If key status is "not check", please check whether the transponder is virgin or not.
- If transponder is virgin, please register the transponder and then go to "Verification of Vehicle Repair" Procedure.

NOTE:
1. Be sure that PIN code is prepared before performing key teaching.
2. If you register the transponder, please register all keys which were already registered with the PIN code.

VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and monitor CURRENT DATA to check No. of Learnt key, ECM and KEY status.
2. Select "Diagnostic Trouble Codes (DTCs)" mode and Clear the DTCs.
3. Are any DTCs present?

YES - Go to the applicable troubleshooting procedure.

NO - System is performing to specification at this time.