Here we go again !!!!!

ABS Sensors are easy they only have 2 wires....

Unplug from the multiplug under the plastic cover behind the wheel and meter across the plug that is connected to the sensor....

Height Sensors:

HAVE A DOOR OPEN and IGNITION OFF AT ALL TIMES....

Attached is a diagram of the PLUG end....you will want to measure the SENSOR, but looking at the Connector diagram, you want to identify Pin 4 as this is the Pot wiper arm....Pins 1 & 5 are the Reference Voltage in and out I believe (I attach the schematic - maybe Datatek or other Electronic guru can offer guidnce).

First I would measure the resistance across Pins 1 & 5 on the sensor to prove the pot winding is fine and note the reading

Second Measure Resistance from Pin 1 to Pin 4 and note the reading - this will read what the resistance is from the Pot Wiper to the Winding in one direction

Thrid Measure Resistance from Pin 4 to Pin 5 and note the reading - this will read what the resistance is from the Pot Wiper to the Winding in the other direction

Do this for all the sensors and compare the readings....any thing out of the ordinary might indicate an issue....

If they are fine, it could be the wiring to the ECU or the ECU itself....

To test the wiring, you will need to gain access to the ECU which is under the dash on the passanger side....

You would then measure the resistance across the pins to each sensor in turn and ensure you get similar readings to the ones you took directly from the Sensors....anything not similar would indicate a problem with the wiring....if they all check out...the next thing is the ECU!!

To check Wiring you will need to:

DISCONNECT BATTERY

Remove the ECU Wiring Multiplug with 51 pins on.

Look at the connector and Identify pins By looking at the colours of the wires (First Letter is the Main Colour and the Second Letter is the Trace Colour):
FL 43,25,32
FR 42,24,33
RL 45,27,51
RR 44,26,50

For FRONT LEFT:
Measure Resistance cross Pins 43 & 32 - should be the same as pins 1 & 5 on sensor
Measure Resistance cross Pins 43 & 25 - Should be the same as pins 1 & 4 on sensor
Measure Resistance cross Pins 32 & 25 - should be the same as pins 4 & 5 on sensor

For FRONT RIGHT:
Measure Resistance cross Pins 42 & 33 - should be the same as pins 1 & 5 on sensor
Measure Resistance cross Pins 42 & 24 - Should be the same as pins 1 & 4 on sensor
Measure Resistance cross Pins 33 & 24 - should be the same as pins 4 & 5 on sensor

For REAR LEFT:
Measure Resistance cross Pins 45 & 51 - should be the same as pins 1 & 5 on sensor
Measure Resistance cross Pins 45 & 27 - Should be the same as pins 1 & 4 on sensor
Measure Resistance cross Pins 51 & 27 - should be the same as pins 4 & 5 on sensor

For REAR RIGHT:
Measure Resistance cross Pins 44 & 50 - should be the same as pins 1 & 5 on sensor
Measure Resistance cross Pins 44 & 26 - Should be the same as pins 1 & 4 on sensor
Measure Resistance cross Pins 50 & 26 - should be the same as pins 4 & 5 on sensor

Any odd readings compared to the Sensor values could indicate a wiring fault....

If they check out, I would be looking at the ECU....

thats an excellent decription, just been looking at the wiring diagrams on rave to try put it into words but couldn't have put it any better than saint .

birchy71 said:

thats an excellent decription, just been looking at the wiring diagrams on rave to try put it into words but couldn't have put it any better than saint .

Click to expand...

Ta - took a bit of thinking about but hopefully will be of use to the poor guy!!

From what saint has said,the abs can affect and cause a shut down , you have just stripped and cleaned brakes are you sure you haven't disturbed a abs sensor do a manuel check that they are seated right home .

Sorry guys that is absolute madness to me i dont understand any of it ill show it my mate hopefully he can make sense of it ??????

sestorious said:

Sorry guys that is absolute madness to me i dont understand any of it ill show it my mate hopefully he can make sense of it ??????

Click to expand...

Best of luck - basically all it is doing is seeing if one of the height sensors is broken inside (the potentiometer winding or the wiper arm that picks off the reference voltage) as you are getting an odd reading...

It also explains how to check the wiring to the ECU multiplug by doing the same measurements and seeing if there is a difference that would indicate damaged wiring....

See what your mate thinks.

defender300td1 said:

From what saint has said,the abs can affect and cause a shut down , you have just stripped and cleaned brakes are you sure you haven't disturbed a abs sensor do a manuel check that they are seated right home .

Click to expand...

So just to clarify,cars suspension wasn't working,you then fixed it and all was good until you had it on ramps to clean rear brakes and now its not working again.In your intial post you said your getting on start up AIR SUSP INACTIVE,so forget what message center lights up at higher speeds because you've already got inactive system and like i said all these systems are interlinked so you will get them at higher speeds regardless.
So you've read faults, dsc is working because you haven't got steering angle fault,but your not getting a reading on OSR height.Too not get a height its either air sus ecu or abs sensor/ecu,but you said everything was ok with system until rear brakes were cleaned( checked compressor and connections,no leaks and new height sensor all around)but you've got a abs canbus error which indicates to me that your OSR abs sensor is either broken,dislodged or misaligned when the brakes were cleaned recently. Now if the sensor is dodgy it wont give the correct reading,which in turn air sus ecu cant get height so produces a fault .
So i'd check that first and if every thing is ok then start checking height sensors but like you've already said they look the part going of pictures provided.

Saint.V8 said:

Ta - took a bit of thinking about but hopefully will be of use to the poor guy!!

Click to expand...

Good write up Ant, I wonder why they used a 6 pin connector when only 3 pins are used?

Right gents my mate has read the write ups an we think we can do these checks ! Only thing is its gonna be in a week or so as he goes away with his family today so thanks so far an please keep your eyes open for me updating this thread thanks again !!!!

DM68 said:

So just to clarify,cars suspension wasn't working,you then fixed it and all was good until you had it on ramps to clean rear brakes and now its not working again.In your intial post you said your getting on start up AIR SUSP INACTIVE,so forget what message center lights up at higher speeds because you've already got inactive system and like i said all these systems are interlinked so you will get them at higher speeds regardless.
So you've read faults, dsc is working because you haven't got steering angle fault,but your not getting a reading on OSR height.Too not get a height its either air sus ecu or abs sensor/ecu,but you said everything was ok with system until rear brakes were cleaned( checked compressor and connections,no leaks and new height sensor all around)but you've got a abs canbus error which indicates to me that your OSR abs sensor is either broken,dislodged or misaligned when the brakes were cleaned recently. Now if the sensor is dodgy it wont give the correct reading,which in turn air sus ecu cant get height so produces a fault .
So i'd check that first and if every thing is ok then start checking height sensors but like you've already said they look the part going of pictures provided.

Click to expand...

All True....

But my thoughts are not with the ABS system as on start up he instantly gets the Air Suspension Inactive warning and no mention of ABS or DSC warning.

He mentions no faults stored in the ABS ECU other than Air Susp. CANbus error and an Articulation fault in the EAS ECU.

When my ABS sensors (Both Fronts Failed at different times) there were stored faults for the offending sensor, and after fitment of one when I hadn't seated it all the way home and not done the bolt up tight enough, I got the warning lights at just over 60mph and an ABS Plausability error fault code stored.....reseated the sensor and all is now well again.

If one sensor is miss reading, I would expect an error code to be logged indicating such, but he has nothing.

As you have correctly said all the systems are internlinked and use eachothers information over the CANbus to control the car so a fault in one affects the others....

If the Air Susp. Inactive is coming up straight away from ignition on without the car moving at all, I think there is an issue with that and the ABS system is going out in sympathy when it cant lower the car at above 60 and the system goes into hard fault!

But we both could be right and we both could be wrong.....these are complex beasts!!

Datatek said:

Good write up Ant, I wonder why they used a 6 pin connector when only 3 pins are used?

Click to expand...

Datatek, it has 6 pin connector because cars with standard halogen lights use 3 pins and cars with xenon lights use 6 pins,so LR are just using a generic connector on the wiring.

Saint.V8 said:

But we both could be right and we both could be wrong.....these are complex beasts!!

Click to expand...

Dont get me wrong Saint, i'm not saying or implying your wrong and i'm right. I'm viewing the situation with whats known and how i would eliminate things before trying something else.

Hopefully with all combined answers this lad can get his car back on the road where it should be, as we both know these cars can even,pardon the pun ' test a saints patience'

And when its finally back on the road it'll add to the collective knowledge of the forum, thus aiding more time driving than fixing

DM68 said:

Dont get me wrong Saint, i'm not saying or implying your wrong and i'm right. I'm viewing the situation with whats known and how i would eliminate things before trying something else.

Hopefully with all combined answers this lad can get his car back on the road where it should be, as we both know these cars can even,pardon the pun ' test a saints patience'

And when its finally back on the road it'll add to the collective knowledge of the forum, thus aiding more time driving than fixing

Click to expand...

Amen to that...

Let your fooking Butler's settle it

Thor1950 said:

Let your fooking Butler's settle it

Click to expand...

Thor, his Butler's gone on his hols and left his employer stranded

DM68 said:

Datatek, it has 6 pin connector because cars with standard halogen lights use 3 pins and cars with xenon lights use 6 pins,so LR are just using a generic connector on the wiring.

Click to expand...

Except we are talking about height sensors not lights, LR are usually keen to save every penny so using a 6 pin when only 3 are needed is a waste. Different connector shapes are used to prevent plugging the wrong thing in the wrong place.

Datatek said:

Except we are talking about height sensors not lights, LR are usually keen to save every penny so using a 6 pin when only 3 are needed is a waste. Different connector shapes are used to prevent plugging the wrong thing in the wrong place.

Click to expand...

We are talking about height sensors and connectors because there's 2 types of height senors, 1 for standard lights and 1 for xenon. On the back of xenon lights is an ecu, which communicates with air sus ecu for headlight leveling between different height settings.

Off at a tangent here but when I had HDC and all the lights light up, it was a bit of corrosion on the spikes in the ABS CPU connection (box at the middle rear of the engine bay). Only happened at times because it was jolted into and out of contact during travel.

cleaned it up, put some contact spray in and all's well for over a year. worth a look?

DM68 said:

We are talking about height sensors and connectors because there's 2 types of height senors, 1 for standard lights and 1 for xenon. On the back of xenon lights is an ecu, which communicates with air sus ecu for headlight leveling between different height settings.

Click to expand...

Is that right? Even if the HID's need different leveling to halogen lights, I don't see how it would affect the type of height sensor, the leveling is done by the EAS ECU. Next you'll be telling me that the rear suspension is raised or lowered to dip the HID's.

Datatek said:

Is that right? Even if the HID's need different leveling to halogen lights, I don't see how it would affect the type of height sensor, the leveling is done by the EAS ECU. Next you'll be telling me that the rear suspension is raised or lowered to dip the HID's.

Click to expand...

Unfortunatly Keith...the Xenons leveling system does use height readings direct from the sensors amd doesn't get the level information from the EAS ECU....which seems odd to me, but that is how it is described....as attached.....