Toyota Tundra Service Manual: Efi Relay

On-vehicle Inspection

ON-VEHICLE INSPECTION

PROCEDURE

1. REMOVE INTEGRATION RELAY

2. INSPECT INTEGRATION RELAY (EFI)

NOTICE:

Some relays are built into the integration relay. The integration relay cannot be disassembled. If there is a malfunction in the circuit of the integration relay, replace the integration relay.
The internal circuit of the integration relay is as shown in the illustration below. Inspect the integration relay using the following procedures.

(a) Measure the resistance of the EFI No. 1 fuse.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
EFI NO. 1 fuse	Always	Below 1 Ω

If the result is not as specified, replace the EFI No. 1 fuse.

(b) Measure the resistance of the EFI relay.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1C-1 - 1B-4

1C-1 - 1B-5

When battery voltage is not applied to terminals 1B-2 and 1B-3

10 kΩ or higher

When battery voltage is applied to terminals 1B-2 and 1B-3

Below 1 Ω

If the result is not as specified, replace the integration relay.

3. INSTALL INTEGRATION RELAY

Toyota Tundra Service Manual > Lane Departure Alert System: Lost Communication with Yaw Rate Sensor Module (U0123,U0126,U0129,U0142,U0155)
DESCRIPTION These DTCs are output when a communication malfunction occurs between the sensors and ECUs. DTC No. Detection Item DTC Detection Condition Trouble Area U0123 Lost Communication with Yaw Rate Sensor Module 3 seconds after the ignition switch is turned to ON, the vehicle is being driven at ...

Toyota Tundra Owners Manual