DESCRIPTION
Each No. 1 headlight ECU sub-assembly and headlight leveling motor communicate via LIN communication.
The headlight leveling motor operates according to power supplied and automatic headlight beam level control signals from its respective No. 1 headlight ECU sub-assembly and sends its operating state to the No. 1 headlight ECU sub-assembly.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
---|---|---|---|---|
B2424 | Headlight Beam Level Control Motor LH Lost Communication |
|
| AFS |
B2425 | Headlight Beam Level Control Motor RH Lost Communication |
|
| AFS |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
Click here
PROCEDURE
1. | 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
|
2. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Wait 10 seconds or more.
(d) Turn the Techstream on.
(e) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(f) Check for DTCs.
Body Electrical > AFS > Trouble CodesOK:
DTC B2424 and B2425 are not output.
Result | Proceed to |
---|---|
OK | A |
NG (DTC B2424 is output) | B |
NG (DTC B2425 is output) | C |
NG (DTC B2424 and B2425 are output) | D |
A | ![]() | USE SIMULATION METHOD TO CHECK |
C | ![]() | GO TO STEP 4 |
D | ![]() | GO TO STEP 7 |
|
3. | INSPECT NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
*a | Component without harness connected (No. 1 Headlight ECU Sub-assembly LH) | - | - |
(a) Remove the No. 1 headlight ECU sub-assembly LH.
Click here
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
A49-20 (LINL) - C-13 (LINLI) | Always | Below 1 Ω |
Result | Proceed to |
---|---|
OK (for TMC Made) | A |
OK (for TMMC Made) | B |
NG | C |
A | ![]() | REPLACE HEADLIGHT UNIT LH |
B | ![]() | REPLACE HEADLIGHT ASSEMBLY LH |
C | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
4. | 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 |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
5. | CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH (LINL TERMINAL SIGNAL OUTPUT) |
*a | Front view of wire harness connector (to No. 1 Headlight ECU Sub-assembly RH) |
(a) Connect the A49 No. 1 headlight ECU sub-assembly LH connector.
(b) Using a Techstream, check the waveform.
OK:
Tester Connection | Condition | Specified Condition |
---|---|---|
A50-20 (LINL) - Body ground | Engine switch on (IG) | Pulse generation |
NG | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
|
6. | INSPECT NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH |
*a | Component without harness connected (No. 1 Headlight ECU Sub-assembly RH) | - | - |
(a) Remove the No. 1 headlight ECU sub-assembly RH.
Click here
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
A50-20 (LINL) - C-13 (LINLI) | Always | Below 1 Ω |
Result | Proceed to |
---|---|
OK (for TMC Made) | A |
OK (for TMMC Made) | B |
NG | C |
A | ![]() | REPLACE HEADLIGHT UNIT RH |
B | ![]() | REPLACE HEADLIGHT ASSEMBLY RH |
C | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH |
7. | 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) or A50-20 (LINL) - Body ground | Always | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
8. | CLEAR DTC |
(a) Connect the A49 No. 1 headlight ECU sub-assembly LH connector.
(b) Connect the Techstream to the DLC3.
(c) Turn the engine switch on (IG).
(d) Turn the Techstream on.
(e) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(f) Clear the DTCs.
Body Electrical > AFS > Clear DTCs
|
9. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Wait 10 seconds or more.
(d) Turn the Techstream on.
(e) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(f) Check for DTCs.
Body Electrical > AFS > Trouble Codes Result | Proceed to |
---|---|
DTC B2425 is output | A |
DTC B2424 and B2425 are output | B |
B | ![]() | GO TO STEP 13 |
|
10. | CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH |
(a) Remove the No. 1 headlight ECU sub-assembly RH.
Click here
(b) Connect the A50 No. 1 headlight ECU sub-assembly RH connector.
|
11. | 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
|
12. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Wait 10 seconds or more.
(d) Turn the Techstream on.
(e) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(f) Check for DTCs.
Body Electrical > AFS > Trouble Codes Result | Proceed to |
---|---|
DTC B2425 is output (for TMC Made) | A |
DTC B2425 is output (for TMMC Made) | B |
DTC B2424 and B2425 are output | C |
A | ![]() | REPLACE HEADLIGHT UNIT RH |
B | ![]() | REPLACE HEADLIGHT ASSEMBLY RH |
C | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH |
13. | CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
(a) Remove the No. 1 headlight ECU sub-assembly LH.
Click here
(b) Connect the A49 No. 1 headlight ECU sub-assembly LH connector.
(c) Connect the A50 No. 1 headlight ECU sub-assembly RH connector.
|
14. | 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
|
15. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Wait 10 seconds or more.
(d) Turn the Techstream on.
(e) Enter the following menus: Body Electrical / AFS / Trouble Codes.
(f) Check for DTCs.
Body Electrical > AFS > Trouble Codes Result | Proceed to |
---|---|
DTC B2424 is output (for TMC Made) | A |
DTC B2424 is output (for TMMC Made) | B |
DTC B2424 and B2425 are output | C |
A | ![]() | REPLACE HEADLIGHT UNIT LH |
B | ![]() | REPLACE HEADLIGHT ASSEMBLY LH |
C | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
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