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:
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE If there are no DTCs but the problem still occurs, check the suspected areas for each problem symptom in the order given in the table below and proceed to the relevant troubleshooting page. Electronically Controlled Brake System Symptom Suspected Area Link ABS warni
Vehicle Control History
VEHICLE CONTROL HISTORY NOTICE: Make sure to record any output Vehicle Control History codes before clearing them and checking the Vehicle Control History again. CHECK VEHICLE CONTROL HISTORY (ROAD SIGN ASSIST SYSTEM) (a) Connect the Techstream to the DLC3. (b) Turn the engine switch on (IG). (c) Tu
