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. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Note |
---|---|---|---|---|
B279A |
Theft Deterrent System Communication Line High Fixation |
Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high. |
|
|
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 |
- |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
PROCEDURE
1. |
CLEAR DTC |
(a) Clear the DTCs.
Powertrain > Engine and ECT > Clear DTCs
|
2. |
CHECK FOR DTC |
(a) Check for DTCs.
Powertrain > Engine and ECT > Trouble CodesHINT:
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B279A is not output.
Result |
Proceed to |
---|---|
B279A is not output |
A |
B279A is output |
B |
A | ![]() |
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 AND BODY GROUND) |
(a) Disconnect the F22 transponder key ECU assembly connector
(b) Disconnect the A38 ECM connector
(c) Measure the resistance according to the value(s) in the table below
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
F22-13 (EFIO) - A38-28 (IMI) |
Always |
Below 1 Ω |
F22-13 (EFIO) - Body ground |
Always |
10 kΩ or higher |
A38-28 (IMI) - Body ground |
Always |
10 kΩ or higher |
NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
5. |
REPLACE TRANSPONDER KEY ECU ASSEMBLY |
(a) Replace the transponder key ECU assembly with a new one.
Click here
|
6. |
CLEAR DTC |
(a) Clear the DTCs.
Powertrain > Engine and ECT > Clear DTCs
|
7. |
CHECK FOR DTC |
(a) Check for DTCs.
Powertrain > Engine and ECT > Trouble CodesHINT:
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B279A is not output.
Result |
Proceed to |
---|---|
B279A is not output |
A |
B279A is output |
B |
A | ![]() |
END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE) |
B | ![]() |
REPLACE ECM |
Toyota CH-R Service Manual > Tire Pressure Warning System: Tire Pressure Monitor ECU Communication Stop (C2179/79)
DESCRIPTION
The main body ECU (multiplex network body ECU) sends signals to the tire pressure
warning ECU and receiver via a direct line.
DTC No.
Detection Item
DTC Detection Condition
Trouble Area
Note
C2179/79
T ...
Toyota CH-R Service Manual > Meter / Gauge System: Precaution
PRECAUTION
FUEL RECEIVER GAUGE OPERATION
(a) OPERATION
The combination meter assembly uses the fuel injection volume signal from the
ECM, fuel sender gauge assembly to detect the amount of fuel remaining in the fuel
tank assembly. Each gauge assembly has a variable resistor whose resistance c ...