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:
Removal
REMOVAL
CAUTION / NOTICE / HINT
HINT:
Use the same procedure for both the LH and RH sides.
The procedure described below is for the LH side.
PROCEDURE
1. REMOVE FRONT BUMPER ASSEMBLY
(See page
)
2. REMOVE HEADLIGHT ASSEMBLY
(a) Apply protective tape around the headlight ...
Transmission Fluid Temperature Sensor "B" Circuit Low Input (P2742,P2743)
DESCRIPTION
The No. 2 ATF temperature sensor is installed in the transmission valve body
assembly.
If the ECM detects an abnormally high ATF temperature near this sensor, it illuminates
the warning indicator.
HINT:
The temperature of ATF easily rises when towing, climbing hills, in
...
System Description
SYSTEM DESCRIPTION
1. SYSTEM DESCRIPTION
HINT:
The skid control ECU is built into the hydraulic brake booster.
(a) ABS (Anti-lock Brake System)
The ABS helps prevent the wheels from locking when the brakes are applied firmly
or when braking on a slippery surface.
(b) Multi-terrain Anti-lock ...
