Diagnostics and testing of steering column switches

Inspection and verification

1. Check the validity of the customer's complaint by using the system.

2. Visually inspect for obvious signs of mechanical or electrical damage.

Visual inspection table

	Electrical factors
	– Fuse(s)
	- Wiring harness
	– Loose or corroded connectors
	– Ignition switch
	– Turn signal/headlight switch and headlight signal switch
	– Windscreen washer/wiper switch

3. If an obvious cause for the problem you have identified or the problem described by the customer is found, correct it before proceeding with further action (if possible).

4. If the cause is not visually obvious, check the malfunction symptom and refer to the Malfunction Symptom Table.

Table of signs of malfunctions

State	Possible Causes	Action
•Ignition switch malfunction	•Ignition switch •Electric circuit •Fuse box	•Proceed to Pinpoint Test A.
•No power supply in the "ACC" position"	•Ignition switch •Fuse box •Electrical circuit(s)	•Go to Pinpoint Test B
•No power supply in the "RUN" position"	•Ignition switch •Fuse(s) •Electrical circuit(s) •Ignition relay	•Go to Pinpoint Test C
•No power supply in START position	•Ignition switch •Electrical circuit(s) •Starter lock relay	•Go to Pinpoint Test D