- With the spring rate switch valve RH not activated, an open signal of the spring rate switch valve RH is detected for 1 second or more.
- With the spring rate switch valve RH activated, a short signal of the spring rate switch valve RH is detected 8 times successively.
| Last Modified: 11-27-2007 | 1.6 C | |
| Service Category: Suspension | Section: Suspension Control System | |
| Model Year: 2008 | Model: LX570 | Doc ID: RM000003BBJ001X |
| Title: SUSPENSION CONTROL: ACTIVE HEIGHT CONTROL SUSPENSION: DESCRIPTION (2008 LX570) | ||
|
DTC |
C1736 |
Front Suspension Control Valve RH Malfunction |
|
DTC |
C1737 |
Front Suspension Control Valve LH Malfunction |
DESCRIPTION
In order to decrease roll angle/pitch angle, the suspension control ECU turns the spring rate switching valve in the front suspension control valve off/on to change the fluid lines when the acceleration sensor or yaw rate sensor signal is input into the suspension control ECU. Normally, the spring rate switching valve is open.
|
DTC Code |
Detection Condition |
Trouble area |
|---|---|---|
|
C1736 |
When either of the following is detected: |
|
|
C1737 |
When either of the following is detected:
|
|
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
- Before performing troubleshooting, inspect the connectors of related circuits.
-
If the suspension control ECU or height control sensor is replaced, the vehicle height offset calibration must be performed
.
HINT:
Power is supplied to the front suspension control valve and No. 1 height control valve from the suspension control ECU. If a short occurs in the power supply circuit in the No. 1 height control valve, DTC C1736 and/or C1737 will be stored. In this case, DTC C1741, C1742, C1743, C1744, C1753, C1754 and/or C1755 will also be stored.
PROCEDURE
|
1. |
PERFORM ACTIVE TEST USING TECHSTREAM (FRONT SPRING RATE SWITCHING VALVE) |
(a) Turn the engine switch off.
(b) Connect the Techstream to the DLC3.
(c) Start the engine and turn the Techstream on.
(d) Enter the following menus: Chassis / AHC / Active Test.
(e) Check the operation of the front spring rate switching valve solenoid when operating the solenoid with the Techstream.
AHC
|
Tester Display |
Test Part |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
FR Gas Spring Switch Valve |
Front spring rate switching valve RH |
ON or OFF |
When the FR Gas Spring Switch Valve item of the Active Test is operated, the FR Gas Spring Switch Valve item of the Data List changes to ON/OFF. |
|
FL Gas Spring Switch Valve |
Front spring rate switching valve LH |
ON or OFF |
When the FL Gas Spring Switch Valve item of the Active Test is operated, the FL Gas Spring Switch Valve item of the Data List changes to ON/OFF. |
OK:
The front spring rate switching valve operates.
|
|
2. |
RECONFIRM DTC OUTPUT |
(a) Clear the DTCs
.
(b) Perform a road test.
(c) Check for DTCs.
Result
|
Result |
Proceed to |
|---|---|
|
DTC is output |
A |
|
DTC is not output |
B |
|
|
3. |
CHECK HARNESS AND CONNECTOR (SUSPENSION CONTROL ECU - FRONT SUSPENSION CONTROL VALVE) |
(a) Disconnect the N9*1 and/or N11*2 front suspension control valve connector.
HINT:
*1: for RH
*2: for LH
(b) Disconnect the K32 ECU connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K32-11 (CRFR) - N9-1 (CRFR) |
Always |
Below 1 Ω |
|
K32-11 (CRFR) - Body ground |
Always |
10 kΩ or higher |
|
K32-23 (CRFL) - N11-1 (CRFL) |
Always |
Below 1 Ω |
|
K32-23 (CRFL) - Body ground |
Always |
10 kΩ or higher |
|
K32-1 (SLB) - N9-2 (SLB) |
Always |
Below 1 Ω |
|
K32-1 (SLB) - N11-2 (SLB) |
Always |
Below 1 Ω |
|
|
4. |
CHECK HARNESS AND CONNECTOR (BODY GROUND BETWEEN ECU - FRONT SUSPENSION CONTROL VALVE) |
(a) Disconnect the K32 ECU connector.
(b) Disconnect the N9*1 and/or N11*2 front suspension control valve connector.
HINT:
*1: for RH
*2: for LH
|
(c) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
|
5. |
INSPECT FRONT SUSPENSION CONTROL VALVE |
(a) Connect the N9 and/or N11 front suspension control valve connector.
|
(b) Disconnect the K32 ECU connector. |
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K32-11 (CRFR) - K32-1 (SLB) |
at 20°C (68°F) |
4.58 to 5.02 Ω |
|
K32-23 (CRFL) - K32-1 (SLB) |
at 20°C (68°F) |
4.58 to 5.02 Ω |
|
|
6. |
CHECK HARNESS AND CONNECTOR (BODY GROUND BETWEEN ECU - NO. 1 HEIGHT CONTROL VALVE) |
(a) Disconnect the N3 No. 1 height control valve connector.
(b) Disconnect the K32 ECU connector.
|
|
(c) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
|
7. |
CHECK HARNESS AND CONNECTOR (NO. 1 HEIGHT CONTROL VALVE - SUSPENSION CONTROL ECU)
|
|
|
|