Testing the relay socket
You replace a relay and nothing changes. The important test was underneath it all along.
What this lesson covers
CORE TEACHING Terminal identification; permanent feed; switched/ECU feed; coil ground; output; terminal tension; burnt pins. PRACTICAL DEMONSTRATIONS AND TESTS Probe socket 30, 85, 86, 87; use test lamp where appropriate; inspect spread terminals; voltage-drop output. ADVANCED / SCAN TOOL LAYER Use scan actuator command to switch coil while watching terminal response. KEY DIAGNOSTIC QUESTIONS Which terminal should be live all the time? Which changes with command? Where does 87 go? MUST-COVER CHECKPOINTS Identify 30/85/86/87/87a from diagram; coil test; control-side test; contact-side loaded test; socket terminal tension; suppression device.
What you will be able to do
You replace a relay and nothing changes. The important test was underneath it all along.
Where it sits in the programme
- Builds on
- Lesson 14: Relay testing
- Feeds into
- Lesson 16: Fuse boards and power distribution modules