Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DBβ LIVE
HOMESERVICE MANUALSTOYOTA20084 RUNNER 2WD V8-4.7L (2UZ-FE)REPAIR AND DIAGNOSISBRAKES AND TRACTION CONTROLANTILOCK BRAKES / TRACTION CONTROL SYSTEMSTESTING AND INSPECTIONSYMPTOM RELATED DIAGNOSTIC PROCEDURESDOWNHILL ASSIST CONTROL INDICATOR LIGHT REMAINS ON
2008 Toyota 4 Runner 2WD V8-4.7L (2UZ-FE)
Downhill Assist Control Indicator Light Remains ON
2008 Toyota 4 Runner 2WD V8-4.7L (2UZ-FE)SECTION Downhill Assist Control Indicator Light Remains ON
BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: Downhill Assist Control Indicator Light Remains ON
Downhill Assist Control Indicator Light Remains ON
DESCRIPTION
The downhill assist control indicator light comes on when the downhill assist control is ready.
HINT: Even if the downhill assist control switch is pressed, the downhill assist control indicator light will blink and downhill assist control will not be activated under the following conditions:
- Transfer is in 2WD or H4 mode.
- VSC system is malfunctioning.
- Temperature of the hydraulic brake booster increases and downhill assist control is temporarily canceled.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE: When replacing the master cylinder solenoid, perform zero point calibration Programming and Relearning.
PROCEDURE
1. INSPECT IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED
(a) Check the skid control ECU connector's connecting condition.
OK:
The connector should be securely connected.
NG -- CONNECT CONNECTOR TO ECU
OK -- Continue to next step.
2. INSPECT BATTERY
(a) Check the battery voltage.
Standard voltage:
11 to 14 V
NG -- INSPECT CHARGING SYSTEM
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - COMBINATION METER)
(a) Disconnect the skid control ECU connector and combination meter connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. INSPECT COMBINATION METER ASSEMBLY
(a) Check the combination meter system Meter / Gauge System.
NG -- REPLACE COMBINATION METER ASSEMBLY
OK -- Continue to next step.
5. INSPECT SKID CONTROL ECU (HDCS TERMINAL)
(a) Disconnect the skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- REPLACE MASTER CYLINDER SOLENOID
NG -- Continue to next step.
6. INSPECT DOWNHILL ASSIST CONTROL SWITCH
(a) Disconnect the downhill assist control switch connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE DOWNHILL ASSIST CONTROL SWITCH
OK -- Continue to next step.
7. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - DOWNHILL ASSIST CONTROL SWITCH)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- CHECK FOR INTERMITTENT PROBLEMS
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.