Lexus ES: Terminals Of Ecu
TERMINALS OF ECU
NOTICE:
- Turning the engine switch on (IG) with connectors disconnected may cause DTCs to be stored. Make sure to clear the DTCs after inspection has been performed.
- Do not apply excessive force to the millimeter wave radar sensor assembly connector.
CHECK MILLIMETER WAVE RADAR SENSOR ASSEMBLY
(a) Measure the voltage and resistance according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A37-8 (IGB) - A37-1 (SGND) | SB - W-B | Power source | Engine switch on (IG) | 11 to 14 V |
| Engine switch off | Below 1 V | |||
| A37-1 (SGND) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
(b) Check for pulses according to the value(s) in the table below.
HINT:
If the waveform is not similar to that shown in the illustration, a malfunction of a CAN bus line, terminating resistor, or the millimeter wave radar sensor assembly is suspected.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A37-5 (CA1P) - A37-1 (SGND) | G - W-B | CAN communication signal | Engine switch on (IG) | Pulse generation (See waveform 1) |
| A37-6 (CA1N) - A37-1 (SGND) | W - W-B | Pulse generation (See waveform 2) | ||
| A37-3 (CA2H) - A37-1 (SGND) | R - W-B | Pulse generation (See waveform 1) | ||
| A37-2 (CA2L) - A37-1 (SGND) | W - W-B | Pulse generation (See waveform 2) |
(1) WAVEFORM 1
.png)
| Item | Content |
|---|---|
| Tester Connection |
|
| Tool Setting | 1 V/DIV., 10 μs/DIV. |
| Condition | Engine switch on (IG) |
HINT:
The waveform varies depending on the CAN communication signal.
(2) WAVEFORM 2
.png)
| Item | Content |
|---|---|
| Tester Connection |
|
| Tool Setting | 1 V/DIV., 10 μs/DIV. |
| Condition | Engine switch on (IG) |
HINT:
The waveform varies depending on the CAN communication signal.
READ NEXT:
Dtc Check / Clear
DTC CHECK / CLEAR CHECK 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 > Front Radar Sens
Freeze Frame Data
FREEZE FRAME DATA DESCRIPTION (a) Whenever a front radar sensor system DTC is stored, the millimeter wave radar sensor assembly stores the current vehicle state as Freeze Frame Data. CHECK FREEZE FRAM
Data List / Active Test
DATA LIST / ACTIVE TEST DATA LIST NOTICE: In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a pa
SEE MORE:
Extension Module Malfunction 2 (B1556)
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On-vehicle Inspection
ON-VEHICLE INSPECTION CAUTION / NOTICE / HINT CAUTION: To prevent injury due to contact with an operating cooling fan, keep your hands and clothing away from the cooling fans when working in the engine compartment with the engine running or the power switch on (IG). PROCEDURE 1. INSPECT ENGINE COOL
