Toyota Tacoma (2015-2018) Service Manual: High Beam Headlight Circuit
DESCRIPTION
The main body ECU (multiplex network body ECU) controls the high beam headlights.
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
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).*1
- *1: w/ Smart Key System
PROCEDURE
|
1. |
PERFORM ACTIVE TEST USING TECHSTREAM (HEAD LIGHT Hi) |
(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 |
|---|---|---|---|
|
Head Light Hi |
High beam headlights |
ON/OFF |
- |
OK:
High beam headlights illuminate.
| OK | .gif) |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
|
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|
2. |
INSPECT DIMMER RELAY |
|
(a) Remove the headlight dimmer relay from the engine room relay block. |
|
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
3 - 5 |
Voltage is not applied between terminals 1 and 2 |
10 kΩ or higher |
|
3 - 5 |
Voltage is applied between terminals 1 and 2 |
Below 1 Ω |
| NG | |
REPLACE DIMMER RELAY |
|
|
3. |
CHECK HARNESS AND CONNECTOR (BATTERY - DIMMER RELAY) |
(a) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Relay terminal 2 - Body ground |
Always |
11 to 14 V |
|
Relay terminal 5 - Body ground |
Always |
11 to 14 V |
| NG | |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
4. |
CHECK HARNESS AND CONNECTOR (DIMMER RELAY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
(a) Disconnect the M6 main body ECU (multiplex network body ECU) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Relay terminal 1 - M6-1 (DIM) |
Always |
Below 1 Ω |
|
M6-1 (DIM) - Body ground |
Always |
10 kΩ or higher |
| OK | |
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
| NG | |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
Door Unlock Detection Switch Circuit
DESCRIPTION
The main body ECU (multiplex network body ECU) detects the condition of each
door unlock detection switch.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
If the main body ECU (mul ...
Low Beam Headlight Circuit
DESCRIPTION
The main body ECU (multiplex network body ECU) controls the low beam headlights.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to thi ...
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
...
Parts Location
PARTS LOCATION
ILLUSTRATION
*A
for Automatic Transmission
*B
for Manual Transmission
*C
for 4WD
-
-
*1
FRONT SPEED SENSOR LH
*2
FRONT SPEED SENSOR RH
...
Fail-safe Chart
FAIL-SAFE CHART
1. FAIL-SAFE FUNCTION
(a) When communication fails in any of the CAN bus lines (communication lines),
a fail-safe function(s) will operate. The fail-safe function that is specified for
each system operates to prevent those systems from malfunctioning.
(b) The following table s ...
