ECU Power Source Circuit
This circuit provides power to operate the transponder key ECU assembly.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
If the transponder key ECU assembly is replaced, register the key and ECU communication ID (See page
).
PROCEDURE
CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - BATTERY AND BODY GROUND)
(a) Disconnect the transponder key ECU assembly connector. |
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(b) Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
|---|---|---|
D22-1 (+B) - Body ground |
Always |
11 to 14 V |
D22-2 (IG) - Body ground |
Ignition switch off |
Below 1 V |
D22-2 (IG) - Body ground |
Ignition switch ON |
11 to 14 V |
Standard Resistance:
Tester Connection | Condition | Specified Condition |
|---|---|---|
D22-16 (GND) - Body ground |
Always |
Below 1 Ω |
*1 |
Front view of wire harness connector (to Transponder Key ECU Assembly) |
| OK | ![]() | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
| NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR, OR REPLACE FUSE |
Test yourself
A quick Toyota Venza quiz: every answer comes with an explanation and a link to the manual page.

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