B2796
THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM (for Hatchback): B2796: No Communication in Immobiliser System
B2796 - No Communication in Immobiliser System
DESCRIPTION
* DTC B2796 is stored when a key is inserted into the ignition key cylinder but no communication occurs between the key and transponder key ECU assembly.
* *: 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 or key, refer to the Registration Engine Immobiliser System (for Hatchback).
* 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) Insert and remove each registered key one at a time, and check for DTC each time Reading and Clearing Diagnostic Trouble Codes.
HINT
* Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
* If DTC B2796 is stored, check for DTCs with the next key after clearing the DTCs.
OK:
DTC B2796 is not output.
Result
B -- CHECK CONNECTION OF CONNECTOR
C -- REPLACE KEY THAT CANNOT START ENGINE
A -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting
3. CHECK CONNECTION OF CONNECTOR
(a) Check the connection of the transponder key ECU assembly and transponder key amplifier connectors.
(b) Visually inspect the terminals of the transponder key ECU assembly and transponder key amplifier connectors.
OK:
Connectors are properly connected.
NG -- CONNECT CONNECTORS PROPERLY
OK -- Continue to next step.
4. CHECK WHETHER ENGINE STARTS
(a) Check that the engine starts with an already registered vehicle key.
OK:
Engine starts normally.
NG -- CHECK TRANSPONDER KEY AMPLIFIER
OK -- Continue to next step.
5. CLEAR DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
6. CHECK FOR DTC
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B2796 is not output.
NG -- CHECK TRANSPONDER KEY AMPLIFIER
OK -- END (CONNECTOR WAS NOT PROPERLY CONNECTED)
7. CHECK TRANSPONDER KEY AMPLIFIER
(a) Using an oscilloscope, check the waveform.
(1) Waveform 1 (Reference)
Measurement Condition
(2) Waveform 2 (Reference)
Measurement Condition
(3) Waveform 3 (Reference)
Measurement Condition
OK:
Waveform is output normally (refer to illustration).
Text in Illustration
Result
B -- CHECK TRANSPONDER KEY AMPLIFIER (VC5)
C -- CHECK TRANSPONDER KEY AMPLIFIER (TXCT)
D -- CHECK TRANSPONDER KEY AMPLIFIER (CODE)
A -- REPLACE TRANSPONDER KEY ECU ASSEMBLY Removal (from 07/2011)
8. CHECK TRANSPONDER KEY AMPLIFIER (VC5)
(a) Disconnect the D140 transponder key amplifier connector.
(b) Using an oscilloscope, check the waveform.
(1) Waveform (Reference)
Measurement Condition
OK:
Waveform is output normally (refer to illustration).
Text in Illustration
NG -- CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)
OK -- REPLACE TRANSPONDER KEY AMPLIFIER Removal (from 07/2011)
9. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)
(a) Disconnect the D140 transponder key amplifier connector.
(b) Disconnect the D139 transponder key ECU assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE TRANSPONDER KEY ECU ASSEMBLY Removal (from 07/2011)
10. CHECK TRANSPONDER KEY AMPLIFIER (TXCT)
(a) Disconnect the D140 transponder key amplifier connector.
(b) Using an oscilloscope, check the waveform.
(1) Waveform (Reference)
Measurement Condition
OK:
Waveform is output normally (refer to illustration).
Text in Illustration
NG -- CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)
OK -- REPLACE TRANSPONDER KEY AMPLIFIER Removal (from 07/2011)
11. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)
(a) Disconnect the D140 transponder key amplifier connector.
(b) Disconnect the D139 transponder key ECU assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE TRANSPONDER KEY ECU ASSEMBLY Removal (from 07/2011)
12. CHECK TRANSPONDER KEY AMPLIFIER (CODE)
(a) Disconnect the D140 transponder key amplifier connector.
(b) Using an oscilloscope, check the waveform.
(1) Waveform (Reference)
Measurement Condition
OK:
Waveform is output normally (refer to illustration).
Text in Illustration
NG -- CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)
OK -- REPLACE TRANSPONDER KEY AMPLIFIER Removal (from 07/2011)
13. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY AMPLIFIER - TRANSPONDER KEY ECU ASSEMBLY)
(a) Disconnect the D140 transponder key amplifier connector.
(b) Disconnect the D139 transponder key ECU assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE TRANSPONDER KEY ECU ASSEMBLY Removal (from 07/2011)