Thread: 20" rim D4 on Border Track, SA

Originally Posted by Graeme

If the compressor cannot operate (eg electrical plug smashed) or the air-line from the compressor is broken preventing any height or reservoir valve pressure increase then a serious suspension fault will occur. However usually if that message occurs then the vehicle is already on its way to the bump-stops, assuming the pilot exhaust valve solenoid is still operational.

An ABS fault does not trigger the 50kph message, only the safe height (access height) message.

So what's the trigger for the 50km/h message Graeme?
I take it "serious suspension fault" with moving to bump stops and the 50km/h message do not go together so I'm confused.

Also confused about what tyres have to do with an apparent suspension fault or how sand dunes are related?

Gary did you sustain some tyre damage and the suspension issue is unrelated (and bad luck)?
More details about what happened would be good.

Regards,
Scott

Originally Posted by DIS4

....car had to be towed back to Melbourne due to suspension fault....
....The car was limited to maximum speed of 50km, partly due to tyre issue....
....heard the suspension vibration....
....There were few sand dunes that I had to push harder to get it past
....It seems me that clearance was an issue and 20" rim with low profile tyre doesn't help....
....cooper types damaged half hour before we exited....

I thought the 50km/h warning was when you have the suspension in off road height, and if you exceed 50km/h without heeding the warning, it drops to normal height.

Originally Posted by sheerluck

I thought the 50km/h warning was when you have the suspension in off road height, and if you exceed 50km/h without heeding the warning, it drops to normal height.

I initially thought of this too but had 40km/h in mind as the limit.
Just double-checked in my GOE booklet and you're right it is 50km/h with a warning at I think 40km/h.
Original issues still a mystery then.

Scott

There are several triggers for the 50 kph message and accompanying attempted lowering but lowering can only occur if the appropriate valves are functioning. Loss of 2 height sensors is one trigger for loss of control of the system and subsequent attempted lowering to the bump-stops. To lower, the corner valves and the pilot exhaust valve must be operational so a disconnected electrical connector at the compressor will prevent the pilot exhaust valve from opening. If the 20A engine bay suspension fuse is removed but not the 5A ignition feed fuse in the passenger fuse panel then the suspension ecu knows that the suspension is not operational but cannot power the valves. The 50 kph message is regularly re-issued whilst the system is not sufficiently functional and ignition power is provided to the suspension ecu.

LR have woken-up to the stupidity of lowering to the bump-stops with the L494 & L405 suspension ecus giving the driver the option not to lower, and presumably the D5 will also have the option.

Edit: My original post was with reference to the maximum speed of 50 kph message rather than a slow or will lower from off-road height message .

Originally Posted by Graeme

My original post was with reference to the maximum speed of 50 kph message rather than a slow or will lower from off-road height message .

My guess is Gary got the maximum speed message as that would be more relevant with the comment about suspension/compressor problem.

Originally Posted by Graeme

The 50 kph is a warning only. If the car isn't already on the bump-stops then removing the 20A suspension system fuse from the engine bay fuse box will prevent it lowering which means that the vehicle can be driven if everything else is OK. A warning beep will occur regularly but removing the 5A suspension system fuse from the passenger fuse box will stop that.

If you don't already have a way to get extra height for off-road use then consider fitting either GOE multi-hole height sensor rods or the LLAMS kit that I produce.

Thanks, Graeme. I tried to get a LLAMS organised for sometime, but thought to be ok on this trip. I might push it too hard on some of sand dune, but one of mates on Colorado without modification, on highway Tyre still pass without problems. I just wonder if I am out of luck or should not race against others, but you would not feel good if a colorado still do better with road tyre.

Originally Posted by LRD414

My guess is Gary got the maximum speed message as that would be more relevant with the comment about suspension/compressor problem.

The full story:
Suspension light turned yellow after I changed tyre, but the spare (255/35R20) is the not same as rest of cooper 275/45R20. That trigger the initial warning, such as ABS, DSC, Parking in yellow. I got suspension light in red after I left border track and drove on high way near Kaniva. It actually warned me the maximum speed to 50k, suspension lower as well.

It is a stupid decision not to have the same spare in time since all local shops had to order in two-three days. One of mates on Land cruiser recon that I should be able to drive back to Melbourne without serious damage. However, the computer might detect the different size of tyre and trigger the warning. This is not the big issue, but compressor will give me more headache now. It is under warranty but one of service guy mentioned that might be out of pockets due to extend of offroad driving. Should I get under body inspection to see if any sign of physical damage? Otherwise, dealer will say offroad damage regardless.

Now I think we understand. Your spare was definitely not up to the job, it was waaaaay undersized. It's a 27" tyre, compared to the others that are 30".