B2799
THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM (for Hatchback): B2799: Engine Immobiliser System Malfunction
B2799 - Engine Immobiliser System Malfunction
DESCRIPTION
This DTC is stored when one of the following occurs: 1) the ECM detects errors in its own communications with the transponder key ECU assembly; 2) the ECM detects errors in the communication lines; or 3) the ECU - ECM communication ID between the transponder key ECU assembly and ECM is different and an engine start is attempted. Before troubleshooting for this DTC, make sure no engine immobiliser DTCs are output. If output, troubleshoot the engine immobiliser DTCs first.
* *: Only output while a malfunction is present.
Vehicle Condition and Fail-safe Operation when Malfunction Detected
Related Data List and Active Test
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
* When replacing the transponder key ECU assembly, refer to the Registration Engine Immobiliser System (for Hatchback).
* When replacing the ECM, refer to the INITIALIZATION Initialization (from 07/2011).
* After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.
PROCEDURE
1. CLEAR DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
2. CHECK FOR DTC
(a) Start the engine.
(b) Wait 10 seconds or more.
(c) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B2799 is not output.
Result
B -- INSPECT ECM (TERMINAL IMO)
C -- GO TO DIAGNOSTIC TROUBLE CODE CHART Engine Immobiliser System (for Hatchback)
A -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting
3. INSPECT ECM (TERMINAL IMO)
(a) Using an oscilloscope, check the waveform.
Text in Illustration
Measurement Condition
OK:
Waveform is output normally (refer to illustration).
Result
B -- INSPECT ECM (IMO TERMINAL VOLTAGE)
C -- REPLACE ECM
A -- Continue to next step.
4. INSPECT ECM (TERMINAL IMI)
(a) Using an oscilloscope, check the waveform.
Text in Illustration
Measurement Condition
OK:
Waveform is output normally (refer to illustration).
Result
B -- REPLACE TRANSPONDER KEY ECU ASSEMBLY
A -- Continue to next step.
5. REGISTER ECU COMMUNICATION ID
(a) Reregister the ECU communication ID Engine Immobiliser System (for Hatchback).
NEXT -- Continue to next step.
6. CHECK WHETHER ENGINE STARTS
(a) Check that the engine starts with an already registered vehicle key.
OK:
Engine starts normally.
NG -- REPLACE ECM
OK -- END (COMMUNICATION ID REGISTRATION WAS DEFECTIVE)
7. INSPECT ECM (IMO TERMINAL VOLTAGE)
(a) Disconnect the A72 ECM connector.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Result
Text in Illustration
B -- REPLACE ECM
A -- Continue to next step.
8. CHECK HARNESS AND CONNECTOR (ECM - TRANSPONDER KEY ECU AND BODY GROUND)
(a) Disconnect the D139 transponder key ECU assembly connector.
(b) Disconnect the A72 ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
9. REPLACE TRANSPONDER KEY ECU ASSEMBLY
(a) Replace the transponder key ECU assembly Removal (from 07/2011).
NEXT -- Continue to next step.
10. REGISTER KEY
(a) Reregister the key Engine Immobiliser System (for Hatchback).
NEXT -- Continue to next step.
11. REGISTER ECU COMMUNICATION ID
(a) Reregister the ECU communication ID Engine Immobiliser System (for Hatchback).
NEXT -- Continue to next step.
12. CHECK WHETHER ENGINE STARTS
(a) Check that the engine starts with an already registered vehicle key.
OK:
Engine starts normally.
NG -- REPLACE ECM Removal (from 07/2011)
OK -- END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE)
13. REPLACE ECM
(a) Temporarily replace the ECM with a new one Removal (from 07/2011).
NEXT -- Continue to next step.
14. REGISTER ECU COMMUNICATION ID
(a) Reregister the ECU communication ID Engine Immobiliser System (for Hatchback).
NEXT -- Continue to next step.
15. CHECK WHETHER ENGINE STARTS
(a) Check that the engine starts with the key.
OK:
Engine starts normally.
NG -- REPLACE TRANSPONDER KEY ECU ASSEMBLY Removal (from 07/2011)
OK -- END (ECM WAS DEFECTIVE)