Power Source Circuit
This circuit provides power to operate the blind spot monitor sensor.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURECHECK HARNESS AND CONNECTOR (BLIND SPOT MONITOR SENSOR RH, BLIND SPOT MONITOR SENSOR LH - BATTERY AND BODY GROUND)
(a) Disconnect the blind spot monitor sensor LH connector. |
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(b) Disconnect the blind spot monitor sensor RH connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Switch Condition | Specified Condition |
|---|---|---|
B12-5 (BLB) - Body ground |
Ignition switch ON |
11 to 14 V |
B12-5 (BLB) - Body ground |
Ignition switch off |
Below 1 V |
B13-5 (BRB) - Body ground |
Ignition switch ON |
11 to 14 V |
B13-5 (BRB) - Body ground |
Ignition switch off |
Below 1 V |
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
|---|---|---|
B12-10 (BLGD) - Body ground |
Always |
Below 1 Ω |
B13-10 (BRGD) - Body ground |
Always |
Below 1 Ω |
*a |
Front view of wire harness connector (to Blind Spot Monitor Sensor LH) |
*b |
Front view of wire harness connector (to Blind Spot Monitor Sensor RH) |
| OK | ![]() |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
| NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
Test yourself
A quick Toyota Tacoma quiz: every answer comes with an explanation and a link to the manual page.

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