Headlight Leveling Control Unit Input Test

NOTE:

Before testing, check for DTCs. If any DTCs are indicated, troubleshoot those DTCs first, and combination light switch circuit is OK.
If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
Before testing, make sure the No. C7 (7.5 A) fuse in the under-hood fuse/relay box is OK.
Before testing, make sure the No. D12 (20 A) fuse in the driver's under-dash fuse/relay box is OK.

1. Turn the vehicle to the OFF (LOCK) mode.

Courtesy of HONDA, U.S.A., INC.

3. 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.

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 all the input tests prove OK, go to step 5.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
9	LT GRN	Under all conditions	Check for continuity between terminal No. 9 and data link connector (DLC) terminal No. 9: There should be continuity.	An open in the SCS wire

5. 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 headlight leveling control unit .
NOTE: After replacing the headlight leveling control unit, do the headlight initial position learning procedure .

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
6	BLU	Vehicle ON mode	Measure the voltage to ground: There should be battery voltage.	Blown No. C7 (7.5 A) fuse in the under-hood fuse/relay box Blown No. D12 (20 A) fuse in the driver's under-dash fuse/relay box An open or high resistance in the wire

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
12	BRN	In all power modes	Measure the voltage to ground: There should be less than 0.2 V.	Poor ground (G401) An open or high resistance in the ground wire
3	BLU	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G401) An open or high resistance in the ground wire
4	PNK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G401) An open or high resistance in the ground wire
5	BLU	Vehicle ON mode, and headlight switch ON	Measure the voltage between terminals No. 5 and No. 4: There should be about 5 V.	Faulty headlight leveling motor An open or high resistance in the wire
4	PNK	Vehicle ON mode, and headlight switch ON
11	ORN	Vehicle ON mode, and headlight switch ON	Measure the voltage between the terminals No. 11 and No. 4: There should be about 0.5 to 4.5 V.	Faulty headlight leveling motor An open or high resistance in the wire
4	PNK	Vehicle ON mode, and headlight switch ON
1	PUR	Vehicle ON mode, and headlight switch ON	Measure the voltage between terminals No. 3 and No. 10: There should be about 5 V. Measure the voltage between terminals No. 1 and No. 3: There should be about 0.5 to 4.5 V.	Faulty rear suspension stroke sensor An open or high resistance in the wire
3	BLU
10	BRN