P1642

DTC P1642 NON-IMMOBILIZER-EMS CONNECTED TO AN IMMOBILIZER

Component Location:

GENERAL DESCRIPTION
The immobilizer system consists of a mutual authentication transponder inside the key head, a stand alone antenna, the BCM unit and the EMS. The BCM unit shall emulate the original immobilizer to EMS protocol as closely as possible.

In the Stand alone immobilizer system, the immobilizer is contained within the BCM. The EMS shall request the BCM for permission to start the vehicle. The BCM shall perform the immobilization functions and reply "start" or no start permission to the EMS.

The communication between the BCM and EMS for the purposes of immobilization for the stand alone will be via the "W Line".

DTC DESCRIPTION
This DTC is displayed "Engine Diagnostic Trouble Codes (DTC)".
This DTC indicates that Non Immobilizer ECM is equipped. (Non Immo ONLY)

DTC Detecting Condition:

Schematic Diagram:

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




2. Select "ENGINE Diagnostic Trouble Codes (DTCs)" mode and Clear the DTC.
3. Is the DTC erased?

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
- The ECM which was equipped must be NON Immobilizer ECM.
- Replace the ECM which has Immobilizer function, and then Go to "Verification of Vehicle Inspection" procedure.

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.