Last Modified: 05-13-2024 |
6.11:8.1.0 |
Doc ID: RM1000000028K9Z |
Model Year Start: 2023 |
Model: GR Corolla |
Prod Date Range: [11/2022 -
] |
Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): B27841C; Antenna Coil Circuit Voltage Out of Range; 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [11/2022 - ] |
DTC
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B27841C
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Antenna Coil Circuit Voltage Out of Range
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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.
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Detection Item
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DTC Detection Condition
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Trouble Area
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Note
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B27841C
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Antenna Coil Circuit Voltage Out of Range
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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*)
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-
Engine switch
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Certification ECU (smart key ECU assembly)
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Wire harness or connector
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DTC output confirmation operation:
except Manual Transaxle
-
With the shift position in P and the electrical key transmitter sub-assembly held near the engine switch, an engine start operation is performed by pressing and holding the engine switch when the transmitter battery is depleted.
for Manual Transaxle
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With the electrical key transmitter sub-assembly held near the engine switch, an engine start operation is performed by pressing and holding the engine switch when the transmitter battery is depleted.
|
-
*: Only output while a malfunction is present.
Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected
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Fail-safe Operation when Malfunction Detected
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except Manual Transaxle
-
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 position in P
for Manual Transaxle
-
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
|
-
|
Related Data List and Active Test
DTC No.
|
Data List and Active Test
|
B27841C
|
-
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WIRING DIAGRAM
CAUTION / NOTICE / HINT
PROCEDURE
1.
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CHECK CONNECTION OF CONNECTOR
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(a) Check that the connectors are properly connected to the engine switch and certification ECU (smart key ECU assembly).
OK:
Connectors are properly connected.
NG |
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CONNECT CONNECTORS PROPERLY
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OK
|
|
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2.
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CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE SWITCH AND BODY GROUND)
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Pre-procedure1
(a) Disconnect the I167 certification ECU (smart key ECU assembly) connector.
(b) Disconnect the I35 engine switch connector.
Procedure1
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
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Specified Condition
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I167-12 (ANT1) - I35-1 (ANT1)
|
Always
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Below 1 Ω
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I167-12 (ANT1) or I35-1 (ANT1) - Other terminals and body ground
|
Always
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10 kΩ or higher
|
I167-13 (ANT2) - I35-7 (ANT2)
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Always
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Below 1 Ω
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I167-13 (ANT2) or I35-7 (ANT2) - Other terminals and body ground
|
Always
|
10 kΩ or higher
|
Post-procedure1
(d) None
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
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OK
|
|
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3.
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CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
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Pre-procedure1
(a) Connect the I167 certification ECU (smart key ECU assembly) connector.
Procedure1
(b) Using an oscilloscope, check the waveform.
*a
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Component with harness connected
(Certification ECU (Smart Key ECU Assembly))
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*b
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Waveform
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OK:
Tester Connection
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Condition
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Tool Setting
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Specified Condition
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I167-12 (ANT1) - I167-29 (E)
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Ignition switch off, electrical key transmitter sub-assembly not in cabin, within 30 seconds of engine switch pressed
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5 V/DIV., 200 ms./DIV.
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Pulse generation
(See waveform)
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I167-13 (ANT2) - I167-29 (E)
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Ignition switch off, electrical key transmitter sub-assembly not in cabin, within 30 seconds of engine switch pressed
|
5 V/DIV., 200 ms./DIV.
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Pulse generation
(See waveform)
|
Post-procedure1
(c) None
OK |
|
REPLACE ENGINE SWITCH
for M20A-FKS: Click here
for G16E-GTS: Click here
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