Tire Pressure Warning System: Overview Scion tC I

Note. When disconnecting the negative (-) battery terminal, initialize the following systems after the terminal is reconnected.

TIRE PRESSURE WARNING SYSTEM NAME

Scheme 1

1. TIRE PRESSURE WARNING SYSTEM PRECAUTION When the tire pressure warning lamp comes on, immediately check the air pressure of all tires and adjust to the specified pressure. AIR PRESSURE SPECIFIED VALUE Tire Tire Size Specified Value Front 215/45 R17 220 kPa (2.2 kgf/cm 2 , 32 psi) Rear 215/45 R17 200 kPa (2.0 kgf/cm 2 , 29 psi) This system requires initialization after changing tires or wheels, or after rotating the tires (See «INITIALIZATION»(ref-224754-S18713437862006031100000) ). Set tire pressure within the specified range before initialization. If the tire pressure is not within the specified range, the tire pressure warning system will not function. In the following cases, the system may not operate normally. A compact spare tire, snow tires, or tire chains are used. The tire pressure is excessively higher than specified, or tire pressure suddenly drops due to bursting or other causes. The vehicle is driven on a slippery road surface such as rough or frozen roads. The vehicle speed is less than 19 mph (30 km/h) or more than 62 mph (100 km/h), and the driving duration is less than 5 minutes. The tires differ in tread pattern or by manufacturer. The tires are not the specified size. The tread wear is very different among the installed tires. During rapid acceleration/deceleration or sharp turns. Towing a trailer. The loading is over the limit or imbalanced. Initialization was not performed correctly after replacing or rotating tires or wheels. The outside temperature is below 32°F (0°C) or above 104°F (40°C).
2. FAIL-SAFE FUNCTION When a system malfunction occurs in the tire pressure warning system, the tire pressure warning lamp blinks. The result of this diagnosis is stored in the skid control ECU.

Scheme 2

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Scheme 5

1. TIRE PRESSURE WARNING SYSTEM DESCRIPTION The tire pressure warning system informs the driver if it detects a low tire pressure. When the tire pressure warning system detects low tire pressure in any of the 4 wheels, which affects safe driving and the tire pressure warning lamp comes on. TIRE PRESSURE SPECIFIED VALUE Tire Tire Size Specified Value Front 215/45 R17 220 kPa (2.2 kgf/cm 2 , 32 psi) Rear 215/45 R17 200 kPa (2.0 kgf/cm 2 , 29 psi) Tire pressure warning system is controlled by the skid control ECU. HINT: When the tire pressure warning reset switch is pressed, the tire pressure warning lamp goes off.
2. TIRE PRESSURE WARNING DISPLAY FUNCTION The tire pressure warning lamp comes on, according to the condition of the tire pressure warning system, as shown in the DIAGNOSIS SYSTEM (See «DIAGNOSIS SYSTEM»(ref-224754-S07075733252006031100000) ).
3. SKID CONTROL ECU Skid control ECU is mounted on the brake actuator assy. The ECU monitors the tire rotation speeds using the vehicle speed sensors. If one of the rotation speeds is different from the others during a certain time, the ECU interprets this as a low tire pressure. The ECU illuminates the tire pressure warning lamp.
4. TIRE PRESSURE WARNING RESET SWITCH Pressing the switch enables initialization of the tire rotation speed data stored in the skid control ECU.
5. VEHICLE SPEED SENSOR The sensor mounted on the suspension axle hub detects the tire rotation speed.
6. STOP LAMP SWITCH ASSY The switch used to detect the depressing brake pedal. The judgement of a low tire pressure is prohibited by depressing the brake pedal.
7. AMBIENT TEMPERATURE SENSOR Ambient temperature is used to correct the judgement of a low tire pressure.
8. DLC3 DLC3 is connected to the skid control ECU. Connecting terminal TS (12) and CG (4) enables entering the test mode. The hand-held tester can be used to enter the test mode (SIGNAL CHECK).