Toyota Tacoma (2015-2018) Service Manual: Taillight Relay Circuit
DESCRIPTION
The main body ECU (multiplex network body ECU) controls the operation of the TAIL relay.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- Inspect the fuses for circuits related to this system before performing the following inspection procedure.
- If the main body ECU (multiplex network body ECU) is replaced, refer
to Registration (See page
.gif)
).*1
- *1: w/ Smart Key System
PROCEDURE
|
1. |
PERFORM ACTIVE TEST USING TECHSTREAM (TAILLIGHT RELAY) |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Main Body / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Main Body|
Tester Display |
Test Part |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Taillight Relay |
Taillight relay |
ON/OFF |
- |
OK:
Taillight relay operates. (Taillights illuminate.)
| OK | .gif) |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
|
.gif)
|
2. |
CHECK HARNESS AND CONNECTOR (BATTERY - DRIVER SIDE JUNCTION BLOCK) |
(a) Disconnect the 1K driver side junction block connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
1K-1 - Body ground |
Always |
11 to 14 V |
| NG | |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
3. |
INSPECT DRIVER SIDE JUNCTION BLOCK |
(a) Remove the driver side junction block (See page
).
(b) Remove the main body ECU (multiplex network body ECU) from the driver side junction block.
Text in Illustration
|
*a |
Component without harness connected (Driver Side Junction Block) |
- |
- |
(c) Connect a positive (+) lead from the battery to terminal 1K-1.
(d) Connect a negative (-) lead from the battery to terminal MB-14 (TRLY).
(e) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
1F-3 - Battery negative terminal |
Always |
11 to 14 V |
| OK | |
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
| NG | |
REPLACE DRIVER SIDE JUNCTION BLOCK |
Engine Switch Illumination Circuit
DESCRIPTION
The illuminated entry system controls the engine switch illumination.
WIRING DIAGRAM
PROCEDURE
1.
READ VALUE USING TECHSTREAM (POWER/ENGINE SW LIGHT)
...
Cargo Light Circuit
DESCRIPTION
The main body ECU (multiplex network body ECU) receives a cargo light information
signal from the deck light switch assembly and door courtesy light switch, and illuminates
the cargo ...
Other materials:
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART
If a trouble code is indicated while checking DTCs, inspect the circuit listed
for that code in the table below, and proceed to the applicable page.
Cruise Control System
DTC Code
Detection Item
MIL
See page
...
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART
Differential System (w/ Differential Lock)
DTC Code
Detection Item
See page
P163B
4WD ECU Malfunction
P17BB
Rear Differential Lock Position SW Stuck OFF
...
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 ...
