Automatic Lighting Control Unit-Sensor Input Test

NOTE: Before testing, make sure the No. A21 (10 A) fuse in the under-hood fuse/relay box is OK.

1.	Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

2.	Disconnect the automatic lighting control unit/sensor 7P connector.

Inspect the connector and socket terminals to be sure they are all making good contact:

	If the terminals are bent, loose, or corroded, repair them as necessary, and recheck the system.
	If the terminals are OK, go to step 4.

With the connector still disconnected, do the following input tests:

	If any test indicates a problem, find and correct the cause, then recheck the system.
	If the terminals are OK, go to step 5.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
5	YEL	Disconnect under-dash fuse/relay box connector T (20P)	Check for continuity between terminal No. 5 and under-dash fuse/relay box connector N (20P) terminal No. 19: There should be continuity.	An open or high resistance in the wire

Reconnect the connector, and do the following input tests:

	If any test indicates a problem, find and correct the cause, then recheck the system.
	If all the input tests prove OK, replace the automatic lighting control unit/sensor.

Cavity

Wire

Test condition

Test: Desired result

Possible cause if desired result
is not obtained

WHT

Under all conditions

Measure the voltage to ground:
There should be battery voltage.

	Blown No. A21 (10 A) fuse in the under-hood fuse/relay box
	Faulty under-dash fuse/relay box
	An open or high resistance in the wire

BRN

In all power modes

Measure the voltage to ground:
There should be less than 0.2 V.

	Poor ground (G506)
	An open or high resistance in the ground wire