Toyota Venza: Push Switch / Key Unlock Warning Switch Malfunction (B2780)

Toyota Venza Service Manual / Theft Deterrent / Keyless Entry / Engine Immobiliser System(w/o Smart Key System) / Push Switch / Key Unlock Warning Switch Malfunction (B2780)

DESCRIPTION

This DTC is stored if the transponder key ECU assembly does not detect that the unlock warning switch assembly is ON even when the ignition switch is ON. Under normal conditions, the unlock warning switch assembly is ON when the ignition switch is ON.

DTC No.	DTC Detection Condition	Trouble Area
B2780	"Unlock warning switch ON" is not detected when the ignition switch is ON.	Wire harness or connector Unlock warning switch assembly Transponder key ECU assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

If the transponder key ECU assembly is replaced, register the key and ECU communication ID (See page ).

PROCEDURE

1.	READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Body Electrical / Immobiliser / Data List.

(e) Read the Data List according to the display on the Techstream.

Immobiliser (Transponder Key ECU Assembly)

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Key SW	Unlock warning switch signal/ON or OFF	ON: Key in ignition key cylinder OFF: No key in ignition key cylinder	-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Key SW

Unlock warning switch signal/ON or OFF

ON: Key in ignition key cylinder

OFF: No key in ignition key cylinder

OK:

On the Techstream screen, the item changes between ON and OFF according to the chart above.

REPLACE TRANSPONDER KEY ECU ASSEMBLY

2.	INSPECT UNLOCK WARNING SWITCH ASSEMBLY

(a) Remove the unlock warning switch assembly (See page ).

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
1 - 2	Switch pushed (Key set)	Below 1 Ω
1 - 2	Switch free (Key removed)	10 kΩ or higher

Tester Connection

Switch Condition

Specified Condition

1 - 2

Switch pushed

(Key set)

Below 1 Ω

1 - 2

Switch free

(Key removed)

10 kΩ or higher

Text in Illustration

*1	Component without harness connected (Unlock Warning Switch Assembly)

REPLACE UNLOCK WARNING SWITCH ASSEMBLY

3.	CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - BODY GROUND)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
D24-2 - Body ground	Always	Below 1 Ω

Text in Illustration

*1	Front view of wire harness connector (to Unlock Warning Switch Assembly)

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - UNLOCK WARNING SWITCH)

(a) Disconnect the transponder key ECU assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
D22-3 (KSW) - D24-1	Always	Below 1 Ω
D22-3 (KSW) - Body ground	Always	10 kΩ or higher
D24-1 - Body ground	Always	10 kΩ or higher

Text in Illustration

Front view of wire harness connector

(to Transponder Key ECU Assembly)

Front view of wire harness connector

(to Unlock Warning Switch Assembly)

REPLACE TRANSPONDER KEY ECU ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

Theft Deterrent System Communication Line High Fixation (B279A)

DESCRIPTION If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck high output (e.g. shorted to +B), the ECM stores this DTC. DTC No. DTC Detection ...

Antenna Coil Open / Short (B2784)

DESCRIPTION The transponder key coil is built into the transponder key amplifier and receives a key code signal from the transponder chip in the key. This signal is amplified by the amplifier, th ...

Other materials about Toyota Venza:

Steering Pad Switch Circuit
DESCRIPTION This circuit sends an operation signal from the steering pad switch assembly to the navigation receiver assembly. If there is an open in the circuit, the audio system cannot be operated using the steering pad switch assembly. If there is a s ...

Crankshaft Position Sensor "A" Circuit (P0335,P0339)
DESCRIPTION The crankshaft position sensor system consists of a crank angle sensor plate and a pickup coil. The sensor plate has 34 teeth and is installed on the crankshaft. The pickup coil is made of wound copper wire, an iron core and magnet. The senso ...

Steering Angle Sensor Initialization Incomplete (C1439/31,C1445/31)
DESCRIPTION The skid control ECU acquires the steering angle sensor zero point every time the ignition switch is turned to ON and the vehicle is driven at 50 km/h (31 mph) or more for approximately 30 seconds. The ECU also stores previous zero points. Wa ...