Entire Combination Meter does not Operate
This circuit is the power source circuit for the meter. This circuit provides two types of power sources, one is a constant power source mainly used as a backup power source, and the other is an IG power source mainly used for signal transmission. The constant power source is mainly used as a backup power source for the meter CPU, however, it is also used for CAN communication. If a voltage of 12 V is not applied to terminal IG+ when turning the ignition switch ON, the indicators will not operate.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
CAUTION:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURECHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BATTERY AND BODY GROUND)
(a) Disconnect the combination meter assembly connector. |
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(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Switch Condition | Specified Condition |
|---|---|---|
C9-20 (IG+) - Body ground |
Ignition switch ON |
11 to 14 V |
C9-19 (B) - Body ground |
Always |
11 to 14 V |
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
|---|---|---|
C9-18 (ES) - Body ground |
Always |
Below 1 Ω |
*a |
Front view of wire harness connector (to Combination Meter Assembly) |
| OK | ![]() |
REPLACE COMBINATION METER ASSEMBLY |
| 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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