Pre-Collision System
PRE-COLLISION: PRE-COLLISION SYSTEM: Power Source Circuit
- Power Source Circuit
DESCRIPTION
This circuit supplies power to the seat belt control ECU.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
1. INSPECT SEAT BELT CONTROL ECU (PGND CIRCUIT)
(a) Disconnect the cable from the negative (-) battery terminal.
CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
NOTICE:
When disconnecting the cable, some system need to be initialized after the cable is reconnected Repair Instruction - Initialization.
(b) Disconnect the seat belt control ECU connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
Text in Illustration
(d) Reconnect the seat belt control ECU connector.
(e) Connect the cable to the negative (-) battery terminal.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (PGND CIRCUIT)
OK -- Continue to next step.
2. INSPECT SEAT BELT CONTROL ECU (+B CIRCUIT)
(a) Disconnect the cable from the negative (-) battery terminal.
CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
NOTICE:
When disconnecting the cable, some system need to be initialized after the cable is reconnected Repair Instruction - Initialization.
(b) Disconnect the seat belt control ECU connector.
(c) Connect the cable to the negative (-) battery terminal.
(d) Measure the voltage according to the value(s) in the table below.
Standard voltage:
Text in Illustration
(e) Disconnect the cable from the negative (-) battery terminal.
(f) Reconnect the seat belt control ECU connector.
(g) Connect the cable to the negative (-) battery terminal.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (+B CIRCUIT)
OK -- Continue to next step.
3. INSPECT SEAT BELT CONTROL ECU (IG1 CIRCUIT)
(a) Disconnect the cable from the negative (-) battery terminal.
CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
NOTICE:
When disconnecting the cable, some system need to be initialized after the cable is reconnected Repair Instruction - Initialization.
(b) Disconnect the seat belt control ECU connector.
(c) Connect the cable to the negative (-) battery terminal.
(d) Measure the voltage according to the value(s) in the table below.
Standard voltage:
Text in Illustration
(e) Disconnect the cable from the negative (-) battery terminal.
(f) Reconnect the seat belt control ECU connector.
(g) Connect the cable to the negative (-) battery terminal.
NG -- INSPECT IG1 RELAY
OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Pre-Collision System
4. INSPECT IG1 RELAY
(a) Remove the IG1 relay from the instrument panel J/B.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
(c) Reinstall the IG1 relay.
NG -- REPLACE IG1 RELAY
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - INSTRUMENT PANEL J/B)
(a) Disconnect the seat belt control ECU connector.
Text in Illustration
(b) Remove the IG1 relay from the instrument panel J/B.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
(d) Reinstall the IG1 relay.
(e) Reconnect the seat belt control ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (SEAT BELT CONTROL ECU - INSTRUMENT PANEL J/B)
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (IG1 RELAY POWER SOURCE CIRCUIT)
(a) Remove the IG1 relay from the instrument panel J/B.
Text in Illustration
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
(c) Reinstall the IG1 relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 RELAY POWER SOURCE CIRCUIT)
OK -- Continue to next step.
7. CHECK HARNESS AND CONNECTOR (IG1 RELAY - BODY GROUND)
(a) Remove the IG1 relay from the instrument panel J/B.
Text in Illustration
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
(c) Reinstall the IG1 relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 RELAY - BODY GROUND)
OK -- Continue to next step.
8. CHECK HARNESS AND CONNECTOR (IG1 RELAY - MAIN BODY ECU)
(a) Disconnect the main body ECU connector.
(b) Remove the IG1 relay from the instrument panel J/B.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Standard Resistance (Check for Short):
(d) Reconnect the main body ECU connector.
(e) Reinstall the IG1 relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 RELAY - MAIN BODY ECU)
OK -- GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START How To Proceed With Troubleshooting