Toyota Tundra Service Manual: Headlight Relay

On-vehicle Inspection

ON-VEHICLE INSPECTION

PROCEDURE

1. INSPECT HEADLIGHT RELAY

(a) Remove the headlight relay from the engine room relay box.

(b) Check the resistance.

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

Standard Resistance:

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

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

Toyota Tundra Service Manual > Engine Immobiliser System (w/o Smart Key System): Theft Deterrent System Presence Detection (B279C)
DESCRIPTION This code is stored when an ECM that is incompatible with the engine immobiliser system is installed to the vehicle. DTC No. Detection Item DTC Detection Condition Trouble Area Note B279C Theft Deterrent System Presence Detection An ECM that is incompatible with the engine immobiliser sy ...

Toyota Tundra Owners Manual