Toyota Sienna Service Manual: Tire Pressure Warning Reset Switch Circuit
DESCRIPTION
The ECU enters the initialization mode and performs initialization automatically, when the tire pressure warning ECU receives the signal from the tire pressure warning reset switch. If the ECU receives the signal, the tire pressure warning light blinks 3 times (1 second on, 1 second off).
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK TIRE PRESSURE WARNING RESET SWITCH FUNCTION
(a) Perform the tire pressure warning reset switch test in TEST MODE PROCEDURE (See page TW-25).
OK: Reset switch ON: Tire pressure warning light comes on.
Reset switch OFF: Tire pressure warning light blinks.
END
2 INSPECT TIRE PRESSURE WARNING RESET SWITCH
(a) Disconnect the tire pressure warning reset switch connector.
(b) Measure the resistance between terminals 1 and 2 of the tire pressure warning reset switch when the tire pressure warning switch is ON and OFF.
Standard resistance 
3 CHECK HARNESS AND CONNECTOR (TIRE PRESSURE WARNING RESET SW - TIRE PRESSURE WARNING ECU)
(a) Disconnect the tire pressure warning reset switch T4 connector and tire pressure warning ECU T15 connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
REPLACE TIRE PRESSURE WARNING ECU (See page TW-87)
Vehicle Speed Signal Error (Test Mode DTC)
DTC C2191/91 Vehicle Speed Signal Error (Test Mode DTC)
DESCRIPTION
The tire pressure warning ECU receives a speed signal from the combination
meter. This DTC is stored
upon entering test mode, a ...
Tire Pressure Warning Light Circuit
DESCRIPTION
If the ECU detects trouble, the tire pressure warning light blinks (comes on
after blinking for 1 minute) and
tire pressure monitor is cancelled at the same time. At this time, the ECU ...
Other materials:
Changing the engine switch positions
“LOCK”
The steering wheel is locked and
the key can be removed. (The key
can be removed only when the
shift lever is in “P”.)
“ACC”
Some electrical components such
as the audio system can be used.
“ON”
All electrical components can be
used.
“START”
...
Circuit inspection
A description of the main areas of each circuit inspection
is shown in the table below.
Item
Description
Circuit Description
The major role, operation of the circuit and its component parts are
explained.
Diagnostic Trouble Code No. and Detection item
Indicates ...
Right Front Wheel Speed Sensor Signal
DESCRIPTION
The speed sensor detects wheel speed and sends the appropriate signals to the
ECU. These signals are
used to control the ABS control system. The front and rear rotors have 48
serrations each.
When the rotors rotate, the magnetic field emitted by the permanent magnet in
t ...
