DESCRIPTION
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
---|---|---|---|---|
U0242 | Lost Communication With Headlamp Control Module "B" |
|
| AFS |
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
---|---|---|---|---|
U0242 | Lost Communication With Headlamp Control Module "B" |
|
| HL AutoLeveling |
Pattern | DTC output part name (Display on Techstream) | Suspected Area (Malfunction Status) |
---|---|---|
Headlight ECU Sub-assembly LH (AFS) | ||
U0242 | ||
○: DTC is output | ||
Pattern 1 | ○ |
|
Pattern | DTC output part name (Display on Techstream) | Suspected Area (Malfunction Status) |
---|---|---|
Headlight ECU Sub-assembly LH (HL AutoLeveling) | ||
U0242 | ||
○: DTC is output | ||
Pattern 1 | ○ |
|
WIRING DIAGRAM
for Multiple Beam Headlight
for Single Beam Headlight
CAUTION / NOTICE / HINT
NOTICE:
Click here
Click here
PROCEDURE
1. | CONFIRM MODEL |
(a) Choose the model to be inspected.
Result | Proceed to |
---|---|
for Multiple Beam Headlight | A |
for Single Beam Headlight | B |
B | ![]() | GO TO STEP 7 |
|
2. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(e) Check for DTCs.
Body Electrical > AFS > Trouble CodesOK:
DTC U0242 is not output.
OK | ![]() | USE SIMULATION METHOD TO CHECK |
|
3. | CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH - NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH) |
(a) Disconnect the A49 No. 1 headlight ECU sub-assembly LH connector.
(b) Disconnect the A50 No. 1 headlight ECU sub-assembly RH connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
A49-22 (LCH) - A50-22 (LCH) | Always | Below 1 Ω |
A49-21 (LCL) - A50-21 (LCL) | Always | Below 1 Ω |
A49-22 (LCH) or A50-22 (LCH) - Body ground | Always | 10 kΩ or higher |
A49-21 (LCL) or A50-21 (LCL) - Body ground | Always | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
4. | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH |
(a) Replace the No. 1 headlight ECU sub-assembly RH with a new one.
Click here
|
5. | CLEAR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(e) Clear the DTCs.
Body Electrical > AFS > Clear DTCs
|
6. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(e) Check for DTCs.
Body Electrical > AFS > Trouble CodesOK:
DTC U0242 is not output.
OK | ![]() | END (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH WAS DEFECTIVE) |
NG | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
7. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / HL AutoLeveling / Trouble Codes.
(e) Check for DTCs.
Body Electrical > HL AutoLeveling > Trouble CodesOK:
DTC U0242 is not output.
OK | ![]() | USE SIMULATION METHOD TO CHECK |
|
8. | CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH - NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH) |
(a) Disconnect the A49 No. 1 headlight ECU sub-assembly LH connector.
(b) Disconnect the A50 No. 1 headlight ECU sub-assembly RH connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
A49-20 (LINL) - A50-20 (LINL) | Always | Below 1 Ω |
A49-20 (LINL) or A50-20 (LINL) - Body ground | Always | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
9. | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH |
(a) Replace the No. 1 headlight ECU sub-assembly RH with a new one.
Click here
|
10. | CLEAR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / HL AutoLeveling / Trouble Codes.
(e) Clear the DTCs.
Body Electrical > HL AutoLeveling > Clear DTCs
|
11. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / HL AutoLeveling / Trouble Codes.
(e) Check for DTCs.
Body Electrical > HL AutoLeveling > Trouble CodesOK:
DTC U0242 is not output.
OK | ![]() | END (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH WAS DEFECTIVE) |
NG | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
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