| Last Modified: 11-20-2023 | 6.11:8.1.0 | Doc ID: RM10000000249GR |
| Model Year Start: 2023 | Model: Camry | Prod Date Range: [08/2022 - ] |
| Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): B279A12; Engine Immobiliser System Circuit Short to Battery; 2023 - 2024 MY Camry [08/2022 - ] | ||
|
DTC |
B279A12 |
Engine Immobiliser System Circuit Short to Battery |
DESCRIPTION
If the communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck high, the ECM will store this DTC.
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Note |
|---|---|---|---|---|
|
B279A12 |
Engine Immobiliser System Circuit Short to Battery |
The communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck high. (1 trip detection logic*) |
|
DTC output confirmation operation:
|
- *: Only output while a malfunction is present.
Vehicle Condition and Fail-safe Operation when Malfunction Detected
|
Vehicle Condition when Malfunction Detected |
Fail-safe Operation when Malfunction Detected |
|---|---|
|
Engine cannot be started |
Engine cannot be started |
Related Data List and Active Test
|
DTC No. |
Data List and Active Test |
|---|---|
|
B279A12 |
- |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- When using the Techstream with the engine switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
-
The smart key system (for Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.
Click here
![2023 - 2024 MY Camry [08/2022 - ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): HOW TO PROCEED WITH TROUBLESHOOTING](/t3Portal/stylegraphics/info.gif)
-
Before replacing the ECM or ID code box (immobiliser code ECU), refer to Registration.
Click here
- After performing repairs, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".
HINT:
When DTC B279A12 and a certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.
PROCEDURE
|
1. |
CHECK CONNECTION OF CONNECTOR |
(a) Turn the engine switch off.
(b) Check that the connectors are properly connected to the ECM and certification ECU (smart key ECU assembly).
OK:
Connectors are properly connected.
| NG |
|
CONNECT CONNECTORS PROPERLY |
|
|
2. |
CHECK WHETHER ENGINE STARTS |
(a) Check that the engine starts.
OK:
Engine starts normally.
| OK |
|
|
|
3. |
CHECK ECM |
|
(a) Measure the voltage according to the value(s) in the table below. Standard Voltage:
|
|
| NG |
|
|
|
4. |
CHECK ID CODE BOX (IMMOBILISER CODE ECU) (TERMINAL EFIO) |
(a) Using an oscilloscope, check the waveform.
|
*a |
Component with harness connected (ID Code Box (Immobiliser Code ECU)) |
*b |
Waveform |
|
*c |
Approximately 160 ms. |
*d |
Approximately 270 ms. |
OK:
|
Tester Connection |
Condition |
Tool Setting |
Specified Condition |
|---|---|---|---|
|
K152-4 (EFIO) - Body ground |
Within 3 seconds of engine start or within 3 seconds of engine switch turned on (IG) after cable disconnected and reconnected to battery |
2 V/DIV., 500 ms./DIV. |
Pulse generation (See waveform) |
| OK |
|
REPLACE ECM for A25A-FKS: Click here
for 2GR-FKS: Click here
|
| NG |
|
|
5. |
CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - ECM) |
(a) Disconnect the A24*1 or A21*2 ECM connector.
- *1: for A25A-FKS
- *2: for 2GR-FKS
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
for A25A-FKS
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K152-4 (EFIO) - A24-26 (IMI) |
Always |
Below 1 Ω |
for 2GR-FKS
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K152-4 (EFIO) - A21-59 (IMI) |
Always |
Below 1 Ω |
| OK |
|
REPLACE ECM for A25A-FKS: Click here
for 2GR-FKS: Click here
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|