DESCRIPTION
The No. 1 headlight ECU sub-assembly operates using the power source voltage input from the IG terminal and ECUB terminal.
The IG terminal power source voltage is supplied by turning the IG1 relay to ON.
The No. 1 headlight ECU sub-assembly receives engine switch on (IG) signals from the main body ECU (multiplex network body ECU) via CAN communication, compares the engine switch on (IG) signal and the power source voltage supply condition of the IG terminal and monitors the result.
for Multiple Beam Headlight DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
---|---|---|---|---|
B242E | Open in IG Circuit |
|
| AFS |
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
---|---|---|---|---|
B242E | Open in IG Circuit |
|
| HL AutoLeveling |
WIRING DIAGRAM
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 4 |
|
2. | 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
|
3. | 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 B242E is not output.
OK | ![]() | USE SIMULATION METHOD TO CHECK |
NG | ![]() | GO TO STEP 6 |
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 / HL AutoLeveling / Trouble Codes.
(e) Clear the DTCs.
Body Electrical > HL AutoLeveling > Clear DTCs
|
5. | 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 / HL AutoLeveling / Trouble Codes.
(f) Check for DTCs.
Body Electrical > HL AutoLeveling > Trouble CodesOK:
DTC B242E is not output.
OK | ![]() | USE SIMULATION METHOD TO CHECK |
|
6. | INSPECT NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH (IG TERMINAL VOLTAGE) |
*a | Front view of wire harness connector (to No. 1 Headlight ECU Sub-assembly LH) |
(a) Disconnect the A49 No. 1 headlight ECU sub-assembly LH connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
A49-4 (IG) - Body ground | Engine switch on (IG) | 11 to 14 V |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
7. | CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH - BODY GROUND) |
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
A49-12 (GND) - Body ground | Always | Below 1 Ω |
OK | ![]() | REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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