In this brief article we are going to discuss the 200 Series Toyota Land Cruiser suspension issues, what the causes are, and how these issues can be effectively dealt with.
Most Common Suspension Problems in the Toyota 200 Series Landcruiser
- AHC (Active Height Control) Unable to lift the vehicle to “HI” setting from ‘N’
- Bouncy Ride
- AHC always in ‘LO’ and not moving to ‘N’ position
- Leaking Shock Absorber
- KDSS Light Coming ON
Does the 200 Series Toyota Land Cruiser have air suspension?
No, the Land Cruiser 200 Series, and, even the latest launched 300 series, do not come with Air Suspension. They come with the coil spring suspension along with ‘Active Variable Suspension’ (AVS) Dampers. The Toyota Prado, however, does come with an Air suspension option.
What suspension does the 200 series Toyota Land Cruiser have?
The Land Cruiser 200 Series or J200 platform was known by multiple names in different markets around the world. It was also called the Lexus LX (North America), Toyota Roraima (Venezuela) and the Toyota Land Cruiser V8 (Europe)
All the 200 Series Land Cruiser models had a basic coil spring suspension; the front suspension with a double-wishbone, independent and the rear suspension with driven-axle, five-link design. The front suspension was newly developed, replacing the previous model 100 Series torsion-bar independent layout. The rear suspension, on the other hand, was very similar to the previous 100 Series arrangement.
Apart from the above standard suspension set-up, the following Advanced systems were also available:
- KDSS(Kinetic Dynamic Suspension System), was available either as standard or as an option depending on the model
- 4-wheel AHC(Active Height Control suspension) with AVS(Adaptive Variable Suspension) were Optional features available in the European market
What are the problems in the Toyota Land Cruiser 200 Series Suspension?
The most common suspension problems with the 200 Series Toyota Land Cruiser are:
AHC (Active Height Control) Unable to lift from ‘N’ to ‘HI’
- When the vehicle is already in ‘Lo’ and ‘N’ is selected, the AHC manages to raise. Lowering from ‘N’ to ‘Lo’ also functions.
- When trying to move to the ‘Hi’ position, the suspension moves only by a minuscule amount.
- The Gas pressure/Fluid pressure seems to not develop beyond the ‘N’ position. There could be 3 possible reasons:
- Similar to the Brake System, over a long usage period, there could be minor depletion of AHC Hydraulic system fluid.
- The “Gas Chamber” connected to the Height Accumulator may be malfunctioning
- Either one or more of the 4 Height Sensors, located at each suspension corner, might be malfunctioning
- Check the Fluid level in the reservoir under the hood. If needed top-up with the OEM provided AHC fluid. Repeat the exercise of trying to select ‘Hi’ and seeing if the vehicle lifts itself.
- In case the earlier measure did not work, then, Replace the “Gas Chamber” and check if the AHC functions.
- In case the “Gas Chamber” replacement did not fix the issue, then try to either recondition or replace the “Height Sensors”
- Ride quality seems bouncy even for very minor bumps
- Shock-absorbers seems normal/newly replaced
- The vehicle suspension lift happens when the AHC Control system signals the “Gas Chamber and Damping Force Control Actuator” to increase the Nitrogen gas pressure in the Shock Absorber, leading to an increase in Shock Absorber length. So, normally the Shock-absorber would have been the first to blame.
- Since the shocks were already verified as properly working, the fault would most likely be with the “Gas Chamber” which ‘HOLDs’ and maintains the Gas Pressure. The Gas Chamber contains a membrane that produces pressure and this deteriorates due to wear and tear.
- Replace all 4 of the Gas Chambers after releasing the hydraulic pressure and bleeding the system. Once fitted, the system will need to be replenished with new Hydraulic Fluid and bleeded to eliminate air bubbles ( similar to brake hydraulics).
AHC always in ‘LO’ and not moving to ‘N’ position
- The vehicle sits at the ‘Lo’ position alone
- When selecting either the ‘N’ or ‘Hi’ position, the suspension does not change in height at all
- In the AHC system, there are 4 sensors located at each of the vehicle corner suspensions. These sensors signal the control system as to the current position of the Ride Height (‘H’, ‘N’ or ‘L’). Every time you select and change the Ride height, these sensors are crucial to the functioning of the AHC.
- If your vehicle has crossed 100k miles then there is a good possibility that these Sensors might be malfunctioning. The Sensor is an assembly consisting of moving parts coupled with Electronics, so there is a possibility that the contacts might be dirty.
- For those who are not much into DIY, replacing these components would be the first choice.
- But for those DIY people, there is one way to avoid replacing the sensor. You could dismantle and rebuild this assembly. It would be suggested to use ‘Brake Fluid’ for cleaning the individual small parts.
AHC does not change height & AVS does not change mode
- Vehicle stays in ‘L’ ride height position
- The AHC ‘off’ lamp blinks and the ‘L’ lamp is illuminated constantly.
- Pressing the AHC ‘off’ button does not change anything.
- Changing the AVS suspension mode from comfort to sport makes no difference in feel. The suspension shock absorbers are stuck in a very stiff setting
- Use a scanner to check for Fault Codes.
- The most probable errors you may get are : c1751 (continuous current to compressor) and c1762 (abnormal oil pressure to pump)
- This clearly indicates a probable issue with the pump
- You can check the pump by removing the control system connector and attaching a jumper wire into the diagnostics connector of the pump to manually test-run the AHC pump. If it does not manage to move any liquid, then it is clear that the pump is one of causes
- You can also inspect the shock-absorbers for any oil stains and test the ‘Gas Chambers’ for pressure
- After inspecting the components mentioned above, start replacing the ones that were damaged/malfunctioning
Leaking Shock Absorber
- The Ride height may be either partially working or completely not working
- Excessive bouncing during driving and doing a ‘Bounce’ test
- Oil Stains on the Shock bottom tube
- Over time, the shock absorber seals and valves wear out due to ageing of Rubber/Polymer wear parts
- Shock absorber replacement with OEM part
KDSS warning light coming ON:
- If all warning lights including ABS come on, then it could be a wiring issue. Try replacing the Driver-side and passenger-side ABS wiring
- The external housing is designed for easy ventilation. It therefore also allows mud, salt and any other road debris to accumulate in the housing. This results in corrosion and then causes a Leakage in the stabilizer control housing assembly.
- If the controller was not the issue, and you hear ‘Clunking’ noises from the suspension then it could be a case of low system pressure.
- Apart from cleaning the underbody, you need to also periodically flush out the housing to prevent mud and or salt from packing accumulating in the area around the control assembly.
- If you observed ‘clunking’ noises from the suspension, then you need to get the KDSS system tested for pressure. It should be closer to 3MPa. Any drop from that pressure means that it allows the ARB to move resulting in clunking noise as well. was below 3 Mpa, then the pressure needs to be corrected.
In this brief article we have discussed the 200 seriesToyota Land Cruiser suspension issues, what the causes are, and how these issues can be effectively dealt with.
Frequently Asked Questions (FAQs):
How reliable is the 200 series Toyota Land Cruiser?
The Land Cruiser 200 Series has, over the last decade, proven to last at least 300,000km in the US market. It is also known from past experience that the LandCruiser has a ‘design’ life of nearly 25 years.
Does Land Cruiser Prado have air suspension?
Yes, the Land Cruiser Prado does have an option of Rear Air Suspension in the High-end Heritage Package