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)
Tire Pressure Warning Light CircuitBlower Motor Circuit
DESCRIPTION
The blower motor is operated by signals from the A/C amplifier. Blower motor
speed signals are
transmitted by changes in the Duty Ratio.
Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle. For
example, if A is the period of
continuity in one cycl ...
Glossary of sae and Toyota terms
This glossary lists all SAE-J1930 terms and abbreviations
used in this manual in compliance with SAE
recommendations, as well as their TOYOTA equivalents.
...
DTC check / clear
1. CHECK DTC (USING INTELLIGENT TESTER)
Checking DTCs.
Connect the intelligent tester to the DLC3.
Turn the ignition switch ON.
Read DTCs by following the prompts on the
tester screen.
HINT:
Refer to the intelligent tester operator's manual
for further deta ...