Last Modified: 11-29-2007 1.6 U
Service Category: Suspension Section: Tire Pressure Monitoring
Model Year: 2008 Model: Sequoia Doc ID: RM0000018KZ00QX
Title: TIRE PRESSURE MONITORING: TIRE PRESSURE WARNING SYSTEM: TERMINALS OF ECU (2008 Sequoia)

TERMINALS OF ECU

HINT:

Inspect the connectors from the back side.

1. CHECK TIRE PRESSURE WARNING ECU



(a) Disconnect the O14 tire pressure warning antenna and receiver connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

H40-12 (RDA) - H40-9 (GND)

G - W-B

Tire pressure warning antenna and receiver signal

Ignition switch ON

11 to 14 V

(c) Connect the O14 tire pressure warning antenna and receiver connector.

(d) Measure the voltage and resistance according to the value(s) in the table below.

Standard

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

H40-1 (CLSW) - H40-9 (GND)

B - W-B

Tire pressure warning reset switch

Ignition switch ON

Tire pressure warning reset switch OFF

8 to 14 V

Ignition switch ON

Tire pressure warning reset switch ON

Below 1.5 V

H40-2 (SPD) - H40-9 (GND)

V - W-B

Vehicle speed signal

Vehicle is running

Pulse generation

(see waveform 1)

H40-3 (TC) - H40-9 (GND)

W - W-B

TC terminal

When terminal TC is not connected

8 to 14 V

H40-5 (IND) - H40-9 (GND)

LG - W-B

Tire pressure warning light output signal

After ignition switch is turned ON, when tire pressure warning light illuminates for 3 seconds

2.2 to 4.4 V

Ignition switch ON

Tire pressure warning light off

Below 0.5 V

H40-6 (RF5V) - H40-9 (GND)

Y - W-B

Tire pressure warning antenna and receiver power source

Ignition switch ON

11 to 14 V

H40-7 (IG) - H40-9 (GND)

Y - W-B

IG power source

Ignition switch ON

11 to 14 V

H40-9 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

H40-10 (SIL) - H40-9 (GND)

L - W-B

Diagnosis tester communication line

Ignition switch ON, when communication is not performed with a tester

8 to 14 V

H40-11 (GND2) - H40-9 (GND)

P - W-B

Tire pressure warning antenna and receiver ground

Always

Below 1 Ω

If the result is not as specified, the ECU may have a malfunction.


(e) Using an oscilloscope, check the waveform 1.

Item

Content

Terminal No. (Symbol)

H40-2 (SPD) - H40-9 (GND)

Tool Setting

5 V/DIV., 200 ms/DIV.

Vehicle Condition

While driving at approximately 20 km/h (12 mph).