Toyota Venza: ECU Power Source Circuit

Toyota Venza Service Manual / U660e Automatic Transmission / Transaxle / Automatic Transaxle System / ECU Power Source Circuit

DESCRIPTION

When the ignition switch is turned to ON, voltage from the ECM's MREL terminal is applied to the EFI MAIN relay. This causes the contacts of the EFI MAIN relay to close, which supplies power to terminal +B of the TCM.

WIRING DIAGRAM

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (TCM - BODY GROUND)

(a) Turn the ignition switch off.

(b) Disconnect the TCM connectors.

Standard Resistance:

Tester Connection	Condition	Specified Condition
B40-8 (E1) - Body ground	Always	Below 1 Ω

Text in Illustration

*1	Front view of wire harness connector (to TCM)

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	INSPECT ECU TERMINAL VOLTAGE (+B TERMINAL)

(a) Disconnect the TCM connectors.

(b) Turn the ignition switch to ON.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
B40-18 (+B) - Body ground	Ignition switch ON	11 to 14 V

Text in Illustration

*1	Front view of wire harness connector (to TCM)

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

3.	CHECK HARNESS AND CONNECTOR (TCM - ENGINE ROOM JUNCTION BLOCK ASSEMBLY)

(a) Turn the ignition switch off.

(b) Disconnect the TCM connector.

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

Standard Resistance (Check for Open):

Tester Connection	Condition	Specified Condition
B40-18 (+B) - 1F-18 (+B)	Always	Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection	Condition	Specified Condition
B40-18 (+B) or 1F-18 (+B) - Body ground	Always	10 kΩ or higher

Text in Illustration

Engine Room Junction Block Assembly

Front view of wire harness connector

(to Engine Room Junction Block Assembly)

Front view of wire harness connector

(to TCM)

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
1F-9 - 1F-18	Always	Below 1 Ω

Text in Illustration

*1	Component without harness connected (Engine Room Junction Block Assembly)

GO TO ECM POWER SOURCE CIRCUIT (ENGINE CONTROL SYSTEM / SFI SYSTEM)

REPLACE ENGINE ROOM JUNCTION BLOCK ASSEMBLY

Transmission Control Switch Circuit

DESCRIPTION When the shift lever is in S and it is moved toward "-" or "+", it is possible to select different shift ranges (1st through 6th ranges). Moving the shift lever tow ...

Automatic Transaxle Unit

...

Other materials about Toyota Venza:

Removal
REMOVAL CAUTION / NOTICE / HINT HINT: Use the same procedure for the LH side and RH side. The following procedure listed is for the LH side. PROCEDURE 1. REMOVE FRONT WHEEL 2. REMOVE FRONT AXLE SHAFT NUT 3. SEPARATE FRONT SPEED SENS ...

Transfer Oil
On-vehicle Inspection ON-VEHICLE INSPECTION PROCEDURE 1. INSPECT TRANSFER OIL (a) Remove the No. 1 transfer case plug and gasket. (b) Check that the oil level is between 0 and 5 mm (0 ...

If your vehicle overheats
The following may indicate that your vehicle is overheating. • The engine coolant temperature gauge reaches the maximum, or a loss of engine power is experienced. (For example, the vehicle speed does not increase.) • Steam comes out from under the hood ...