DTC P0504-2B: Brake Switch "A"/"B" Signal Cross Coupled [11/2018 - 08/2020]: Procedure
- CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY)
*a Front view of wire harness connector
(to Stop Light Switch Assembly)- Disconnect the stop light switch assembly connector.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition A40-7 (B) - Body ground Always 11 to 14 V Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - BATTERY)
Result:
OK
See step 2
- CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY)
*a Front view of wire harness connector
(to Stop Light Switch Assembly)- Disconnect the stop light switch assembly connector.
- Turn the ignition switch to ON.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition A40-6 (B) - Body ground Ignition switch ON 11 to 14 V Result
Proceed to OK NG
Result:
NG
See step 6
Result:
OK
See step 3
- CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - BODY GROUND)
- Disconnect the stop light switch assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A40-2 (GND) - Body ground Always Below 1 Ω Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 4
- CHECK TERMINAL VOLTAGE (STP AND ST1- VOLTAGE)
*a Brake Pedal Depressed *b Brake Pedal Released *c Front view of wire harness connector
(to ECM)- - - Disconnect the ECM connector.
- Turn the ignition switch to ON.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Brake Pedal Operation Specified Condition A24-22 (ST1-) - Body ground Released 7.5 to 14 V Depressed Below 1.5 V A24-21 (STP) - Body ground Released Below 1.5 V Depressed 7.5 to 14 V Result
Proceed to OK NG
Result:
OK
REPLACE ECM. Refer to REMOVAL [11/2018 - 08/2020]
Result:
NG
See step 5
- CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ECM)
- Disconnect the stop light switch assembly connector.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A40-5 (L) - A24-22 (ST1-) Always Below 1 Ω A40-3 (L) - A24-21 (STP) Always Below 1 Ω A40-5 (L) or A24-22 (ST1-) - Body ground and other terminals Always 10 kΩ or higher A40-3 (L) or A24-21 (STP) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to REMOVAL [11/2018 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - STOP LIGHT SWITCH ASSEMBLY)
- Disconnect the instrument panel junction block assembly connector.
- Disconnect the stop light switch assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 4F-15 - A40-6 (B) Always Below 1 Ω 4F-15 or A40-6 (B) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 7
- CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND)
- Disconnect the instrument panel junction block assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 4D-3 - Body ground Always Below 1 Ω Result
Result Proceed to OK (w/ Smart Key System) A OK (w/o Smart Key System) B NG C
Result:
B
See step 10
Result:
C
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
A
See step 8
- CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))
- Disconnect the instrument panel junction block assembly connector.
- Disconnect the certification ECU (smart key ECU assembly) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 4A-17 - G54-17 (IG1D) Always Below 1 Ω 4A-17 or G54-17 (IG1D) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 9
- CHECK SMART KEY SYSTEM
- Check the Smart Key System.
Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - 08/2020]
Result
Proceed to OK NG
Result:
OK
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to REMOVAL [11/2018 - 02/2019] , or refer to REMOVAL [02/2019 - 10/2019] , or refer to REMOVAL [10/2019 - 08/2020]
Result:
NG
REPAIR SMART KEY SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - 08/2020]
- Check the Smart Key System.
- CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IGNITION SWITCH ASSEMBLY)
- Disconnect the instrument panel junction block assembly connector.
- Disconnect the ignition switch assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 4A-17 - G28-8 (IG1) Always Below 1 Ω 4A-17 or G28-8 (IG1) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 11
- CHECK ECM POWER SOURCE CIRCUIT
- Check the ECM power source circuit.
Refer to ECM Power Source Circuit [11/2018 - 08/2020]
Result
Proceed to OK NG
Result:
OK
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to REMOVAL [11/2018 - 02/2019] , or refer to REMOVAL [02/2019 - 10/2019] , or refer to REMOVAL [10/2019 - 08/2020]
Result:
NG
REPAIR ECM POWER SOURCE CIRCUIT. Refer to ECM Power Source Circuit [11/2018 - 08/2020]
- Check the ECM power source circuit.