DESCRIPTION
The electrical key and tire pressure monitoring system receiver assembly is used to receive radio waves related to the entry functions of the electrical key transmitter sub-assembly. The certification ECU (smart key ECU assembly) decodes the requested electrical key transmitter sub-assembly operation by identifying a key code based on the radio waves received via the electrical key and tire pressure monitoring system receiver assembly. The electrical key and tire pressure monitoring system receiver assembly receives a signal from the electrical key transmitter sub-assembly and sends signals to the main body ECU (multiplex network body ECU) through the certification ECU (smart key ECU assembly). (ex. If a door lock operation is requested, the certification ECU (smart key ECU assembly) sends a door lock command to the main body ECU (multiplex network body ECU)).
DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
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B1242 | Wireless Door Lock Tuner Circuit Malfunction |
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WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
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PROCEDURE
1. | CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
(a) Disconnect the R23 electrical key and tire pressure monitoring system receiver assembly connector.
*a | Component with harness connected (Certification ECU (Smart Key ECU Assembly)) | - | - |
(b) Measure the voltage and resistance and check for pulses according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
R1-19 (RDAM) - J41-18 (E) | always | 11 to 14 V |
R1-18 (RCO) - J41-18 (E) | always | Below 1 V → 4.5 to 5.5 V pulse generation at regular intervals |
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J41-18 (E) - Body ground | Always | Below 1 Ω |
OK | ![]() | REPLACE ELECTRICAL KEY AND TIRE PRESSURE MONITORING SYSTEM RECEIVER ASSEMBLY |
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2. | CHECK HARNESS AND CONNECTOR (ELECTRICAL KEY AND TIRE PRESSURE MONITORING SYSTEM RECEIVER ASSEMBLY - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) |
(a) Disconnect the R1 and J41 certification ECU (smart key ECU assembly) connectors.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
R1-19 (RDAM) - R23-2 (DATA) | Always | Below 1 Ω |
R1-18 (RCO) - R23-8 (+5) | Always | Below 1 Ω |
R23-12 (GND) - Body ground | Always | Below 1 Ω |
R23-2 (DATA) or R1-19 (RDAM) - Body ground | Always | 10 kΩ or higher |
R23-8 (+5) or R1-18 (RCO) - Body ground | Always | 10 kΩ or higher |
OK | ![]() | REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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