Lexus ES: Lost Communication with Wiper ECU LIN (B1245)
DESCRIPTION
The main body ECU (multiplex network body ECU) and windshield wiper motor assembly communicate via LIN communication. The main body ECU (multiplex network body ECU) stores this DTC if communication becomes abnormal.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Memory | DTC Output from |
|---|---|---|---|---|---|
| B1245 | Lost Communication with Wiper ECU LIN |
|
| ○ | Main Body |
WIRING DIAGRAM
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CAUTION / NOTICE / HINT
NOTICE:
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
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PROCEDURE
| 1. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Main Body / Trouble Codes.
(e) Check for DTCs.
Body Electrical > Main Body > Trouble Codes| Result | Proceed to |
|---|---|
| Only DTC B1245 is output | A |
| DTC B1245 and B1373 are output | B |
| B | .gif) | GO TO B1373 |
|
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| 2. | CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - WINDSHIELD WIPER MOTOR ASSEMBLY) |
(a) Disconnect the G36 main body ECU (multiplex network body ECU) connector.
(b) Disconnect the A38 windshield wiper motor assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G36-3 (LIN3) - A38-2 (LIN) | Always | Below 1 Ω |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
| 3. | CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
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| *a | Component without harness connected (Main Body ECU (Multiplex Network Body ECU) |
(a) Check for voltage and pulses according to the value(s) in the table below.
Standard Voltage:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| G36-3 (LIN3) - Body ground | Power switch off | Below 1 V |
| Power switch on (IG) | Pulse generation |
| NG | | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
|
| 4. | CHECK HARNESS AND CONNECTOR (POWER SOURCE - WINDSHIELD WIPER MOTOR ASSEMBLY) |
(a) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| A38-4 (+B) - Body ground | Power switch on (IG) | 11 to 14 V |
| Less than approximately 60 seconds after power switch turned off | 11 to 14 V | |
| Approximately 60 seconds after power switch turned off | Below 1 V |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
| 5. | CHECK HARNESS AND CONNECTOR (WINDSHIELD WIPER MOTOR ASSEMBLY - BODY GROUND) |
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| A38-1 (GND) - Body ground | Always | Below 1 Ω |
| OK | | REPLACE WINDSHIELD WIPER MOTOR ASSEMBLY |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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Inspection
INSPECTION PROCEDURE 1. INSPECT AND ADJUST BRAKE BOOSTER PUSH ROD NOTICE: Make the adjustment with no vacuum in the brake booster assembly. (Depress the brake pedal several times with the engine stopped.) HINT:
Adjustment of the brake booster push rod is required when the brake master cylinder su
