LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 1993 >> SC 400 >> Repair and Diagnosis >> Electrical >> Starter >> On-Vehicle Testing >> Starter Relay Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Starter Relay Test

NOTE: Starter relays are part of the theft deterrent system. When the theft deterrent system is activated, a contact inside the theft deterrent ECU is opened. This creates an open circuit on the ground side of the starter relay, making the starter inoperative. If starter relay tests okay, go to STARTER RELAY CIRCUIT TEST  to check theft deterrent system starter cutout (if necessary). Unlock driver's door with key to cancel starter cutout BEFORE checking starter relay circuit.
  1. Locate and remove starter relay from relay block near driver's side wheelwell in engine compartment. Ensure continuity exists between terminals No. 1 and 2. See Fig 1. No continuity should exist between terminals No. 3 and 5. If continuity is not as specified, replace relay.
  2. Apply battery voltage across terminals No. 1 and 2. Continuity should now exist between terminals No. 3 and 5. If continuity is not as specified, replace relay. If continuity is okay, check starter relay circuit. See STARTER RELAY CIRCUIT TEST .
Fig 1: Testing Starter Relay
G93B01646Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002