DESCRIPTION
The No. 1 headlight ECU sub-assembly operates the low beam fan to cool the headlight LED unit in order to prevent the headlight LED unit from overheating.
Illuminates the low beam headlights and continuously operates the low beam fan.
The No. 1 headlight ECU sub-assembly monitors the pulse signals from the FANP terminal when the low beam fans are operating.
HINT:
If B243D or B243E is output, the No. 1 headlight ECU sub-assembly performs low beam headlight dimming control.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
---|---|---|---|---|
B243D | Left Low Beam Fan Malfunction |
|
| AFS |
B243E | Right Low Beam Fan Malfunction |
|
| 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) Operate the light control switch to turn on the low beam headlights and wait 120 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 B243D and B243E are not output.
Result | Proceed to |
---|---|
OK | A |
NG (DTC B243D is output) | B |
NG (DTC B243E is output) | C |
A | ![]() | USE SIMULATION METHOD TO CHECK |
C | ![]() | GO TO STEP 6 |
|
3. | CHECK HEADLIGHT UNIT LH |
(a) Interchange the headlight unit LH with RH and connect the connectors.
Click here
|
4. | 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
|
5. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Operate the light control switch to turn on the low beam headlights and wait 120 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 B243D is output | A |
DTC B243E is output (for TMC Made) | B |
DTC B243E is output (for TMMC Made) | C |
A | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
B | ![]() | REPLACE HEADLIGHT UNIT LH |
C | ![]() | REPLACE HEADLIGHT ASSEMBLY LH |
6. | CHECK HEADLIGHT UNIT RH |
(a) Interchange the headlight unit RH with LH and connect the connectors.
Click here
|
7. | 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
|
8. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Operate the light control switch to turn on the low beam headlights and wait 120 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 B243E is output | A |
DTC B243D is output (for TMC Made) | B |
DTC B243D is output (for TMMC Made) | C |
A | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH |
B | ![]() | REPLACE HEADLIGHT UNIT RH |
C | ![]() | REPLACE HEADLIGHT ASSEMBLY RH |
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