DESCRIPTION
When an open or short circuit is detected in the antenna coil built into the transponder key coil, the transponder key ECU assembly stores this DTC.
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Note |
---|---|---|---|---|
B2784 |
Antenna Coil Open / Short |
Any of the following conditions is met:
|
|
|
Vehicle Condition |
|||
---|---|---|---|
Pattern 1 |
Pattern 2 |
||
Diagnosis Condition |
Always |
○ |
○ |
Malfunction Status |
The antenna coil in the transponder key coil is open. |
○ |
- |
The antenna coil in the transponder key coil is shorted. |
- |
○ |
|
Detection Time |
- |
- |
|
Number of Trips |
1 trip |
1 trip |
HINT:
DTC will be output when conditions for either of the patterns in the table above are met.
Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected |
Fail-safe Operation when Malfunction Detected |
---|---|
Engine cannot be started |
- |
DTC No. |
Data List and Active Test |
---|---|
B2784 |
Antenna Coil Status |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
PROCEDURE
1. |
CLEAR DTC |
(a) Clear the DTCs.
Body Electrical > Immobiliser > Clear DTCs
|
2. |
CHECK FOR DTC |
(a) Check for DTCs.
Body Electrical > Immobiliser > Trouble CodesHINT:
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B2784 is not output.
Result |
Proceed to |
---|---|
B2784 is not output |
A |
B2784 is output |
B |
A | ![]() |
USE SIMULATION METHOD TO CHECK |
|
3. |
CHECK CONNECTION OF CONNECTOR |
(a) Check that the connectors are properly connected to the transponder key coil.
|
4. |
CLEAR DTC |
(a) Clear the DTCs.
Body Electrical > Immobiliser > Clear DTCs
|
5. |
CHECK FOR DTC |
(a) Check for DTCs.
Body Electrical > Immobiliser > Trouble CodesHINT:
Before checking for DTCs, perform "DTC Output Confirmation Operation" procedure.
OK:
DTC B2784 is not output.
Result |
Proceed to |
---|---|
B2784 is not output |
A |
B2784 is output |
B |
A | ![]() |
END (CONNECTOR WAS NOT CONNECTED PROPERLY) |
|
6. |
CHECK TRANSPONDER KEY COIL (OUTPUT) |
(a) Using an oscilloscope, check the waveform.
*a |
Component with harness connected (Transponder Key Coil) |
*b |
Waveform 1 |
*c |
Waveform 2 |
- |
- |
Item |
Content |
---|---|
Tester Connection |
F79-1 (ANT1) ←→ Body ground |
Tool Setting |
20 V/DIV., 2 s./DIV. |
Condition |
Within 3 seconds of inserting key into ignition key cylinder |
Item |
Content |
---|---|
Tester Connection |
F79-5 (ANT2) ←→ Body ground |
Tool Setting |
20 V/DIV., 2 s./DIV. |
Tool Setting |
Within 3 seconds of inserting key into ignition key cylinder |
OK:
Waveform is similar to that shown in the illustration
OK | ![]() |
REPLACE TRANSPONDER KEY COIL |
|
7. |
CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - TRANSPONDER KEY COIL AND BODY GROUND) |
(a) Disconnect the F22 transponder key ECU assembly connector.
(b) Disconnect the F79 transponder key coil connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
F22-4 (ANT1) - F79-1 (ANT1) |
Always |
Below 1 Ω |
F22-15 (ANT2) - F79-5 (ANT2) |
Always |
Below 1 Ω |
F22-4 (ANT1) - Body ground |
Always |
10 kΩ or higher |
F79-1 (ANT1) - Body ground |
Always |
10 kΩ or higher |
F22-15 (ANT2) - Body ground |
Always |
10 kΩ or higher |
F79-5 (ANT2) - Body ground |
Always |
10 kΩ or higher |
NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
8. |
REPLACE TRANSPONDER KEY ECU ASSEMBLY |
(a) Replace the transponder key ECU assembly with a new one.
Click here
HINT:
Refer to Registration.
Click here
NOTICE:
Key ID code registration is necessary when replacing the transponder key ECU assembly.
Click here
|
9. |
CLEAR DTC |
(a) Clear the DTCs.
Body Electrical > Immobiliser > Clear DTCs
|
10. |
CHECK FOR DTC |
(a) Check for DTCs.
Body Electrical > Immobiliser > Trouble CodesHINT:
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B2784 is not output.
Result |
Proceed to |
---|---|
B2784 is not output |
A |
B2784 is output |
B |
A | ![]() |
END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE) |
B | ![]() |
REPLACE TRANSPONDER KEY COIL |
Toyota CH-R Service Manual > Front Drive Shaft Assembly: Reassembly
REASSEMBLY
PROCEDURE
1. INSTALL FRONT DRIVE SHAFT DUST COVER LH
(a) Using a steel plate and a press, install a new front drive shaft
dust cover LH.
NOTICE:
The dust cover should be completely installed.
Be careful not to damage the front drive shaft dust co ...
Toyota CH-R Service Manual > Immobiliser System(w/ Smart Key System): Engine Immobiliser System Malfunction (B2799)
DESCRIPTION
If there is a communication malfunction between the ECM and ID code box (immobiliser
code ECU), or when the communication ID codes do not match, the ECM stores this
DTC.
DTC No.
Detection Item
DTC Detection Condition
Trouble Area
...