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Problem Symptoms Table

If a normal code is displayed during the DTC check but the problem still occurs, check the circuits for each problem symptom in the order given in the table below and proceed to the relevant troubleshooting reference.

PROBLEM SYMPTOMS REFERENCE

Symptom Suspected area
Lifting up position of height control indicator light does not change according to operation of height control switch 1. Check that the height control switch is not OFF.
2. Check the DTC.
3. Perform the INPUT SIGNAL CHECK.
Vehicle height control function does not operate 1. Check the power source circuit of the ECU.
2. Check if it is included in the inhibited conditions of the height control. (Rough road judgement, differential lock, etc.)
3. Check the indicator light.
4. Check the DTC.
5. Perform the HEIGHT CONTROL OPERATION TEST.
6. Perform the INPUT SIGNAL CHECK.
When the following 1. to 6. are all normal and the problem is still occurring, replace ECU.
Vehicle height control operates, but the vehicle height does not raise to N to HI position. 1. Check that the loading weight does not exceed the predetermined value.
2. Check if any heavy object such as a winch is installed.
3. Check for a shortage of the fluid.
4. Check the DTC.
5. Perform the INPUT SIGNAL CHECK.
6. Check the front and rear shock absorber fluid pressure.
7. Check the vehicle height. (Height control sensor link)
Vehicle height raises, but vehicle height does not go down to N to LO position 1. Check that the vehicle weight is extremely light.
2. Check if there is anything caught in the absorber and coil spring.
3. Check the DTC.
4. Perform the INPUT SIGNAL CHECK.
5. Check the front and rear shock absorber fluid pressure.
6. Check the vehicle height. (Height control sensor link)
Vehicle height is extremely low when vehicle is parked Check the fluid leakage of the gas chamber, shock absorber, etc. and if it is normal, replace the control valve assembly. HINT: Vehicle height may go down because of the atmosphere temperature change when vehicle is parked.
Vehicle leans to the right or left. 1. Check if the luggage is loaded with a slant.
2. Check the DTC.
3. Adjust the vehicle height.
4. Check the front and rear shock absorber fluid pressure.
5. Check the control valve assembly. (Front and rear gate valve)
6. Check fluid clog in the fluid line and shock absorber, etc.
Vehicle height raise control requires a long time 1. Check that the loading weight does not exceed the predetermined value.
2. Check that the vehicle weight is extremely light.
3. Check the DTC.
4. Check the front and rear shock absorber fluid pressure
5. Check the vehicle height. (Height control sensor link)
6. Check that the fluid pressure of the height control accumulator is not lost.
When the followings 1. to 6. are all normal and the problem is still occurring, replace the AHC pump motor. HINT: Vehicle raise control may require a long time in case that the ambient temperature is -15 (5) or less or the accumulation pressure of the height control accumulator is not completed.
Vehicle height down control requires a long time 1. Check that the vehicle weight is extremely light.
2. Check the front and rear shock absorber fluid pressure.
3. Check the vehicle height. (Height control sensor link)
When the followings 1. to 3. are all normal and the problem is still occurring, replace the control valve assembly. HINT: Vehicle height down control may require a long time in case that the ambient temperature is 15 (5) or less.
Vehicle leans to the front or rear. 1. Check that the height control switch is not OFF.
2. Check fluid leakage. (Gas chamber, shock absorber, etc.)
3. Check the DTC.
4. Check the vehicle height. (Height control sensor link)
When the followings 1. to 4. are all normal and the problem is still occurring, replace the control valve assembly.
Vehicle goes down leaning. 1. Check air leakage of the gas chamber. (Check the fluid level change of the reservoir tank.)
2. Perform the DAMPING FORCE CONTROLLING CONDITION CHECK.
When the followings 1. to 2. are all normal and the problem is still occurring, replace the control valve assembly.
Abnormal noise sounds from AHC system. 1. Check interference of the fluid line.
2. Check interference of the AHC pump and motor.
When the followings 1. to 2. are all normal and the problem is still occurring, replace the pump attenuator.
Vehicle ride is uncomfortable. 1. Check the power source circuit of the ECU.
2. Check the DTC.
3. Perform the DAMPING FORCE CONTROLLING CONDITION CHECK.
4. Perform the INPUT SIGNAL CHECK.
5. Check the resistance of the damping force control actuator.
6. Check air leakage of the gas chamber. (Check the fluid level change of the reservoir tank.)
7. Check the front and rear chock absorber fluid pressure.
When 1. to 7. are all normal and the problem is still occurring, replace the shock absorber. HINT: Vehicle ride may be uncomfortable soon after the starting when the ambient temperature is -10 (14) or less because the fluid viscosity is high.
Vehicle ride is too soft. 1. Check the power source circuit of the ECU.
2. Check the DTC.
3. Perform the DAMPING FORCE CONTROLLING CONDITION CHECK.
4. Perform the INPUT SIGNAL CHECK.
5. Check the resistance of the damping force control actuator.
When 1. to 5. are all normal and the problem is still occurring, replace the damping force control actuator or shock absorber.
Vehicle steering roll is different from right and left turn. 1. Check if the luggage are loaded with a slant.
2. Check the power source circuit of the ECU.
3. Check the DTC.
4. Perform the DAMPING FORCE CONTROLLING CONDITION CHECK.
5. Perform the INPUT SIGNAL CHECK.
6. Check the resistance of the damping force control actuator.
7. Check air leakage of the gas chamber. (Check the fluid level change of the reservoir tank.)
When 1. to 7. are all normal and the problem is still occurring, replace the damping force control actuator or shock absorber.
Vehicle braking dive and starting squat are large. 1. Check the power source circuit of the ECU.
2. Check the DTC.
3. Perform the DAMPING FORCE CONTROLLING CONDITION CHECK.
4. Perform the INPUT SIGNAL CHECK.
5. Check the resistance of the damping force control actuator.
When 1. to 5. are all normal and the problem is still occurring, replace the damping force control actuator or shock absorber.
DTC check cannot be done. 1. Check the height control OFF indicator circuit.
2. Check the TC terminal circuit.
3. Check the power source circuit of the ECU.
INPUT SIGNAL CHECK cannot be done. 1. Check the TS terminal circuit.
2. Check the power source circuit of the ECU.
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