Toyota Tacoma (2015-2018) Service Manual: ECU Power Source Circuit
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
|
1. |
INSPECT BATTERY |
(a) Check the battery voltage.
Standard voltage:
11 to 14 V
| NG | .gif) |
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY |
|
.gif)
|
2. |
CHECK HARNESS AND CONNECTOR (+B AND IG TERMINAL) |
(a) Turn the ignition switch off.
|
(b) Disconnect the 4 wheel drive control ECU connector. |
|
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
F13-21 (+B) - Body ground |
Always |
11 to 14 V |
|
F12-4 (IG) - Body ground |
Ignition switch ON |
11 to 14 V |
|
*a |
Front view of wire harness connector (to 4 Wheel Drive Control ECU) |
| NG | |
REPAIR OR REPLACE HARNESS OR CONNECTOR (+B AND IG CIRCUIT) |
|
|
3. |
CHECK HARNESS AND CONNECTOR (GND TERMINAL) |
(a) Turn the ignition switch off.
|
(b) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
| OK | |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
| NG | |
REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT) |
4WD Control Switch Circuit
WIRING DIAGRAM
PROCEDURE
1.
CONFIRM PROBLEM SYMPTOM
(a) Confirm the problem symptoms.
Result
Result
Proceed to
The 4WD ind ...
Other materials:
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
HINT:
Use the table below to help determine the cause of problem symptoms.
If multiple suspected areas are listed, the potential causes of the symptoms
are listed in order of probability in the "Suspected Area" column of the
table. Check each sy ...
Ignition Hold Monitor Malfunction (B2271)
DESCRIPTION
This DTC is stored when a malfunction in the IG circuit or IG hold circuit in
the certification ECU (smart key ECU assembly) is detected.
HINT:
When the cable is disconnected and reconnected to the negative (-) battery terminal,
the power source mode returns to the state it was in ...
Malfunction of ID-BOX Recognition (B278D)
DESCRIPTION
When the certification ECU (smart key ECU assembly) detects an input signal indicating
that the vehicle is equipped with an ID code box even though the ID code box is
not registered, the certification ECU (smart key ECU assembly) stores this DTC.
DTC Code
DTC ...
