Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota Yaris. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

When replacing the tire pressure warning ECU, read the transmitter IDs stored in the old ECU using a Techstream and write them down before removal.
It is necessary to perform registration (See REGISTRATION ) of the transmitter IDs into the tire pressure warning ECU after the ECU has been replaced.

CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECU AND BODY GROUND)

Disconnect the D78 ECU connector.

Fig 1: Checking Harness And Connector (Combinationn Meter - ECU And Body Ground)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the D1 meter connector.

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

Standard resistance

RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
D78-5 (IND) - D1-6 (TIRE)	Always	Below 1 Ω
D78-5 (IND) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

INSPECT COMBINATION METER

Disconnect the D78 ECU connector.

Fig 2: Identifying D78 ECU Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Turn the ignition switch to ON, and check if the tire pressure warning light illuminates.

OK:

Tire pressure warning light illuminates

Result

RESULT CHART

Result	Proceed to
OK	A
NG (for Hatchback)	B
NG (for Sedan)	C

B: REPLACE COMBINATION METER (See REMOVAL )

C: REPLACE COMBINATION METER (See REMOVAL )

A: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See PROBLEM SYMPTOMS TABLE )