DESCRIPTION
When an open or short circuit is detected in the transponder key amplifier coil built into the engine switch, the certification ECU (smart key ECU assembly) stores this DTC. This DTC is also stored as a history DTC.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Note |
---|---|---|---|---|
B2784 | Antenna Coil Open / Short | The transponder key amplifier coil built into the engine switch is open (see below) or shorted (determined by communication with certification ECU (smart key ECU assembly)). (1 trip detection logic*)
|
| DTC output confirmation operation:
|
Vehicle Condition when Malfunction Detected | Fail-safe Operation when Malfunction Detected |
---|---|
Engine cannot be started when transmitter battery is depleted by holding electrical key transmitter sub-assembly near engine switch and pressing and holding engine switch with shift lever in P | - |
DTC No. | Data List and Active Test |
---|---|
B2784 | - |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
PROCEDURE
1. | CLEAR DTC |
(a) Clear the DTCs.
Body Electrical > Smart Access > Clear DTCs
|
2. | CHECK FOR DTC |
(a) Perform "DTC Output Confirmation Operation" procedure.
(b) Check for DTCs.
Body Electrical > Smart Access > Trouble CodesOK:
DTC B2784 is not output.
OK | ![]() | USE SIMULATION METHOD TO CHECK |
|
3. | CHECK ENGINE SWITCH (OUTPUT) |
(a) Using an oscilloscope, check the waveform.
*a | Component with harness connected (Engine Switch) | *b | Waveform |
*c | Waveform (detail) | - | - |
Measurement Condition:
Tester Connection | Condition | Tool Setting | Specified Condition |
---|---|---|---|
J14-8 (CODE) - J14-6 (AGND) | Engine switch off, engine switch pressed with electrical key transmitter sub-assembly held near engine switch* | 1 V/DIV., 20 ms./DIV. | Pulse generation (See waveform) |
2 V/DIV., 100 μs./DIV. | Pulse generation (See waveform (detail)) |
OK:
The waveform is similar to that shown in the illustration
NG | ![]() | REPLACE ENGINE SWITCH |
|
4. | REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
(a) Replace the certification ECU (smart key ECU assembly) with a new one.
Click here
|
5. | REGISTER ECU COMMUNICATION ID |
(a) Register the ECU communication ID code.
Click here
|
6. | CLEAR DTC |
(a) Clear the DTCs.
Body Electrical > Smart Access > Clear DTCs
|
7. | CHECK FOR DTC |
(a) Perform "DTC Output Confirmation Operation" procedure.
(b) Check for DTCs.
Body Electrical > Smart Access > Trouble CodesOK:
DTC B2784 is not output.
OK | ![]() | END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) |
NG | ![]() | REPLACE ENGINE SWITCH |
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