Toyota Tacoma 2015-2018 Service Manual: Theft Deterrent System Communication Line High Fixation (B279A,B279A12)
DESCRIPTION
If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck high (e.g. shorted to +B), the ECM stores this DTC.
|
DTC No. |
DTC Detection Condition |
Trouble Area |
DTC Output Confirmation Operation |
|---|---|---|---|
|
B279A*1 |
Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high. |
|
Turn the ignition switch to ON and wait 6 seconds. |
|
B279A12*2 |
Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high. |
|
Turn the ignition switch to ON and wait 6 seconds. |
- *1: for 2TR-FE
- *2: for 2GR-FKS
|
Vehicle Condition when Malfunction Detected |
Fail-safe Operation when Malfunction Detected |
|---|---|
|
Engine cannot be started (initial ignition occurs and engine cranks, then ignition stops) |
Engine cannot be started |
|
DTC No. |
Data List and Active Test |
|---|---|
|
B279A*1 |
- |
|
B279A12*1 |
- |
- *1: for 2TR-FE
- *2: for 2GR-FKS
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- If the transponder key ECU assembly or ECM is replaced, refer to Registration
(See page
.gif)
). - After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".
PROCEDURE
|
1. |
CLEAR DTC |
(a) Clear the DTCs (See page ).
|
.gif)
|
2. |
CHECK DTC OUTPUT |
(a) Perform "DTC Output Confirmation Operation" procedure.
(b) Check for DTCs (See page ).
|
Result |
Proceed to |
|---|---|
|
DTC B279A (for 2TR-FE) or B279A12 (for 2GR-FKS) is output |
A |
|
DTC B279A (for 2TR-FE) or B279A12 (for 2GR-FKS) is not output |
B |
| B | .gif) |
USE SIMULATION METHOD TO CHECK |
|
|
3. |
CHECK CONNECTION OF CONNECTOR |
(a) Check that the connectors are properly connected to the ECM and transponder key ECU assembly.
OK:
Connectors are properly connected.
| NG | |
CONNECT CONNECTORS PROPERLY |
|
|
4. |
CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM) |
(a) Disconnect the T10 transponder key ECU assembly connector.
(b) Disconnect the E14*1 or E20*2 ECM connector.
- *1: for 2GR-FKS
- *2: for 2TR-FE
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
T10-13 (EFIO) - E14-8 (IMI)*1 |
Always |
Below 1 Ω |
|
T10-13 (EFIO) or E14-8 (IMI) - Body ground*1 |
Always |
10 kΩ or higher |
|
T10-13 (EFIO) - E20-10 (IMI)*2 |
Always |
Below 1 Ω |
|
T10-13 (EFIO) or E20-10 (IMI) - Body ground*2 |
Always |
10 kΩ or higher |
- *1: for 2GR-FKS
- *2: for 2TR-FE
| NG | |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
5. |
REPLACE TRANSPONDER KEY ECU ASSEMBLY |
(a) Replace the transponder key ECU assembly with a new one (See page
).
|
|
6. |
CLEAR DTC |
(a) Clear the DTCs (See page ).
|
|
7. |
CHECK FOR DTC |
(a) Perform "DTC Output Confirmation Operation" procedure.
(b) Check for DTCs (See page ).
|
Result |
Proceed to |
|---|---|
|
DTC B279A (for 2TR-FE) or B279A12 (for 2GR-FKS) is not output |
A |
|
DTC B279A is output (for 2TR-FE) |
B |
|
DTC B279A12 is output (for 2GR-FKS) |
C |
| A | |
END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE) |
| B | |
REPLACE ECM |
| C | |
REPLACE ECM |
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART
HINT:
If a trouble code is stored during the DTC check, inspect the trouble areas listed
for that code. For details of the code, refer to "See page" below.
...
Theft Deterrent System Presence Detection (B279C,B279C95)
DESCRIPTION
If an ECM that is incompatible with the engine immobiliser system is installed,
the ECM stores this DTC.
DTC No.
DTC Detection Condition
Trouble Area
...
Other materials:
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
HINT:
Use the table below to help determine the cause of problem symptoms.
If multiple suspected areas are listed, the potential causes of the symptoms
are listed in order of probability in the "Suspected Area" column of the
table. Check each sy ...
Inspection
INSPECTION
PROCEDURE
1. INSPECT AUTO HIGH BEAM SWITCH
*a
Component without harness connected
(Auto High Beam Switch)
(a) Check the resistance.
(1) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester C ...
On-vehicle Inspection
ON-VEHICLE INSPECTION
PROCEDURE
1. CHECK FUEL PUMP ASSEMBLY OPERATION
(a) Check fuel pressure.
(1) Connect the Techstream to the DLC3.
(2) Start the engine.
(3) Turn the Techstream on.
(4) Enter the following menus: Powertrain / Engine / Active Test / Control the
Target Fuel Pressure.
(5) ...