| Last Modified: 11-29-2007 | 1.6 J | |
| Service Category: Engine/Hybrid System | Section: Cruise Control | |
| Model Year: 2008 | Model: Sequoia | Doc ID: RM00000295M004X |
| Title: CRUISE CONTROL: DYNAMIC LASER CRUISE CONTROL SYSTEM: DESCRIPTION (2008 Sequoia) | ||
|
Laser Sensor Power Source Circuit |
DESCRIPTION
This circuit provides power to the laser radar sensor. The laser radar sensor emits radio waves towards an object in front and measures the distance and direction of the object by receiving the beam reflections. Based on the reflections, the sensor calculates the difference in speed between the vehicle and the object in front. This data is transmitted to the distance control ECU. The ECM recognizes the laser radar sensor via terminals LGND. If an open circuit occurs in the wire harness between terminals LGND, the ECM cannot recognize the laser radar sensor. The ECM will stop the control of the vehicle-to-vehicle distance control mode and only the constant speed control mode can be used.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
|
1. |
INSPECT DISTANCE CONTROL ECU (IGB VOLTAGE) |
|
(a) Disconnect the A26 laser radar sensor connector. |
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
A26-5 (IGB) - Body ground |
Ignition switch ON |
11 to 14 V |
(c) Reconnect the laser radar sensor connector.
|
|
2. |
CHECK HARNESS AND CONNECTOR (LASER RADAR SENSOR - ECM AND BODY GROUND) |
|
(a) Disconnect the A27 connector from the ECM. |
(b) Disconnect the A26 connector from the laser radar sensor.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A27-44 (LGND) - A26-1 (LGND) |
Always |
Below 1 Ω |
|
A26-1 (LGND) - Body ground |
Always |
10 kΩ or higher |
|
A26-2 (SGND) - Body ground |
Always |
Below 1 Ω |
(d) Reconnect the ECM and laser radar sensor connector.
|
|
3. |
CHECK HARNESS AND CONNECTOR (LASER RADAR SENSOR - DISTANCE CONTROL ECU) |
|
(a) Disconnect the A43 distance control ECU connector. |
(b) Disconnect the A26 laser radar sensor connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A26-5 (IGB) - A43-13 (IGB) |
Always |
Below 1 Ω |
|
A43-13 (IGB) - Body ground |
Always |
10 kΩ or higher |
(d) Reconnect the ECU and laser radar sensor connector.
|
|
|