Disco 3 (LR3) Air Suspension Fault

Hi All,

Been a while since my last post.

Every so often while driving my Discovery 3 2009 a brake fault occurred and the suspension lowered. To clear this I had to switch the engine off and start it again then it would be ok for a week or so then happen out the blue again.

I have had an absolute nightmare trying to resolve the fault replacing valve blocks and compressor as well as checking for leaks.

I am now at a stage of replacing the Discovery 3 Air Suspension ECU Module Land Rover RQT500170 2004 to 2009. I believe this is located and accessed by removing the battery and tray a walk through would be welcomed if anyone has it?

If this doesn't work I am at a total loss as its beyond my capabilities now on where next to look.

let me know your thoughts please guys and if any of you have come across this problem.

Best Regards

Hi, you should check the fault code first with dedicated scantool not change the ECU just like that...what if it's a sensor or wiring issue? Based on the code you have the steps described in the attachment

sierrafery said:

Hi, you should check the fault code first with dedicated scantool not change the ECU just like that...what if it's a sensor or wiring issue? Based on the code you have the steps described in the attachment

Click to expand...

Thanks for this I will start with the wiring for corrosion

Wiring to where? cos it's a huge variety of wires and connectors in that vehicle... do you have an ECU related fault code which made you suspect it?

Brake light switch
Brake light bulbs

Level sensors and their wiring

Not all faults give codes, and not all codes mean there is an actual fault!

lynall said:

Brake light switch
Brake light bulbs

Level sensors and their wiring

Not all faults give codes, and not all codes mean there is an actual fault!

Click to expand...

As above.

Hugy said:

Every so often while driving my Discovery 3 2009 a brake fault occurred and the suspension lowered. To clear this I had to switch the engine off and start it again then it would be ok for a week or so then happen out the blue again.

I have had an absolute nightmare trying to resolve the fault replacing valve blocks and compressor as well as checking for leaks.

I am now at a stage of replacing the Discovery 3 Air Suspension ECU Module Land Rover RQT500170 2004 to 2009. I believe this is located and accessed by removing the battery and tray a walk through would be welcomed if anyone has it?

If this doesn't work I am at a total loss as its beyond my capabilities now on where next to look.

let me know your thoughts please guys and if any of you have come across this problem.

Click to expand...

You've said it happens when you brake, so there's the breadcrumb trail, and the above advice is where to start looking.

It's unlikely to be the EAS module, or the valve blocks.
The EAS module needs to be configured to the vehicle anyway, so unless you have advanced diagnostic equipment to do that, it's not a goer.

Off side rear lever sensor wiring, common fault repair kits on the bay. Corrosion in the loom sensor end.
Could be others not likley ecu

sierrafery said:

Wiring to where? cos it's a huge variety of wires and connectors in that vehicle... do you have an ECU related fault code which made you suspect it?

Click to expand...

Sorry I will get the code first and use the PDF document and go through the recommendations. I will let you know how I get on once I have the code......thanks again mate.

lynall said:

Brake light switch
Brake light bulbs

Level sensors and their wiring

Not all faults give codes, and not all codes mean there is an actual fault!

Click to expand...

I have changed the brake light switch already so can rule that out. My brake light bulbs are working but have not checked the level sensor wiring yet so thanks mate for your help.

biketeacherdave said:

Off side rear lever sensor wiring, common fault repair kits on the bay. Corrosion in the loom sensor end.
Could be others not likley ecu

Click to expand...

Thanks mate, I will hold off on the ECU for now and check the wiring once I have a fault code from a guy i know who pops down with his plug in machine.

Nodge68 said:

As above.


You've said it happens when you brake, so there's the breadcrumb trail, and the above advice is where to start looking.

It's unlikely to be the EAS module, or the valve blocks.
The EAS module needs to be configured to the vehicle anyway, so unless you have advanced diagnostic equipment to do that, it's not a goer.

Click to expand...

Hi, no it happens when mainly when reversing or in slow moving traffic on an incline.

Ok guys I have a fault code U0416-86 and looking at the PDF attached at the top it says under that code check ABS system and DTC's.
Whats DTC's stand for and has anyone got a workshop manual on file i can refer to?

Hugy said:

Hi, no it happens when mainly when reversing or in slow moving traffic on an incline.

Click to expand...

Sounds like a height sensor or wiring then.

Hugy said:

Ok guys I have a fault code U0416-86 and looking at the PDF attached at the top it says under that code check ABS system and DTC's.
Whats DTC's stand for and has anyone got a workshop manual on file i can refer to?

Click to expand...

I think u codes are info only.
So I would say you need access to a better code reader, as it should be able to read abs system on its own.

DTC is trouble code, I have it in my head as digital trouble code!

If you are keeping the car you really need a code reader, dirt cheap ones only read engine codes, better ones read every system, Iirc the D3 has something like 20 ecus.
IID by Gap is the best, but also the most expensive, excellent resale value so may seem dear but cost of ownership will be the same as a cheaper one.
Icarsoft reads all the same systems as the IID but it cannot programme like the IID, which is not the big issue some people like to make out it is, Icarsoft is also 1/4 the price of the IID.

lynall said:

I think u codes are info only.
So I would say you need access to a better code reader, as it should be able to read abs system on its own.

DTC is trouble code, I have it in my head as digital trouble code!

If you are keeping the car you really need a code reader, dirt cheap ones only read engine codes, better ones read every system, Iirc the D3 has something like 20 ecus.
IID by Gap is the best, but also the most expensive, excellent resale value so may seem dear but cost of ownership will be the same as a cheaper one.
Icarsoft reads all the same systems as the IID but it cannot programme like the IID, which is not the big issue some people like to make out it is, Icarsoft is also 1/4 the price of the IID.

Click to expand...

Ok I ll have to call into a local garage and get this checked out as my head now is all over lol. Wish I new someone in the newcastle area who could help.
Cheers for the advice pal

That fault code is meaningless

I ll have to get it sorted at a garage at a massive cost no doubt........nightmare!!

Hugy said:

I ll have to get it sorted at a garage at a massive cost no doubt........nightmare!!

Click to expand...

I don't see why, honestly did a little bit and check those height sensors and wiring repair kits

Hugy said:

I ll have to get it sorted at a garage at a massive cost no doubt........nightmare!!

Click to expand...

Join the D3forum , and beg/bribe someone to come and plug into your car.
Th Gap IID tool is vin locked ie one car, but cans till read all the systems on other cars.
The icarsoft will cost much less than getting a garage to sort the issue.

Hi Guys,

I have an update on where I am at the moment. So I took out the integrated transfer case module and noticed some corrosion on the left hand plug and connectors. I cleaned them all up and inside the case and so far the fault has not came back but its only been a week.
I will still look to get someone in to read the codes or pop into land rover and bite the bullet if and when the fault comes back up. I will also check those height sensors and can see the wiring kits are cheap on ebay and easy to replace.

Thanks again everyone for your help and advice...........I will keep you updated as I go along.