ECU Power Source Circuit

DESCRIPTION

This is the power source for the tire pressure warning ECU.

WIRING DIAGRAM
CAUTION / NOTICE / HINT

NOTICE:

• When replacing the tire pressure warning ECU, read the transmitter IDs stored in the old ECU using the Techstream and write them down before removal.

• It is necessary to perform registration (See page ) of the transmitter IDs into the tire
  pressure warning ECU after the ECU has been replaced.

PROCEDURE

1. INSPECT FUSE (ECU-IG NO. 2)

(a) Remove the ECU-IG No. 2 fuse from the driver side junction block.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
ECU-IG No. 2 fuse	Always	Below 1 Ω

NG

REPLACE FUSE

OK

1. INSPECT IGNITION RELAY NO. 1

(a) Remove the IG1 relay from the driver side junction block.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3 - 5	Battery voltage is not applied between terminals 1 and 2	10 kΩ or higher
	Battery voltage is applied between terminals 1 and 2	Below 1 Ω

NG

REPLACE IGNITION RELAY NO. 1

OK

1. CHECK HARNESS AND CONNECTOR (ECU - BATTERY AND BODY GROUND)

(a) Disconnect the D31 ECU connector.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
D31-7 (IG) - Body ground	Ignition switch ON	11 to 14 V
	Ignition switch off	Below 1 V

Text in Illustration

*1	Front view of wire harness connector (to Tire Pressure Warning ECU)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
D31-9 (GND) - Body ground	Always	Below 1 Ω

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR