Air Suspension Problem
 

I recently purchased an x5 4.8is 2004 model a week later the air suspension inactive has come up, the car is high on the front left and the height adjust buttons green light has gone off but if you rest the fault via diagnostic computer it all starts to work suspension goes up and down but after about 30 miles inactive again the errors read are height invalid and something about a valve (can't find the paper I wrote the fault codes on).

Any advice like where the sensors are on the car what I should try first...

Mr Q

Give us the code first.

Symptom typical of bad height sensor. These are user verifiable with a multimeter. Somewhere on here I put the pin codes and related. In a nutshell you have 3 lines for the air suspension. Ground, 5v source, and a variable voltage based on position. Runs between about 1, and about 4, volts.

Some height sensors also have outputs to the LCM for the HID aiming, so be cognizant of that of you have 6 wires vs 3 at a given connector.

You can disconnect the arm on the height sensor and back probe the wires easily.

If you have INPA it's easier since it tell you real time what the height sensor is reporting.

Typical fault is when the voltage for the height stays low and unchanging. Car tries to raise but voltage doesn't increase as expected. You get a fault.

Common reason for this is the shaft seal on the height sensor wears over the years, and water intrusion can occur. Then corrosion, then failure.

If you don't have a way to diagnose, and your symptom is suspension inactive and one wheel jacked up out of kilter from the rest, start with the easy to check item - height sensor on that corner.

If you have INPA, you can manually put the heights where you want them, then set it to ignore plausibility checks (or something like that; I forget exact terminology). This will keep the car at the height you set (assuming no leaks and stuff; it won't self-correct in this mode). That way you can drive around as usual every day until part shows up and you feel like changing it out. Then put it back into normal operation and clear fault. All happy. :D

By the way, this mode is the easiest way to experiment with different ride heights and stuff, too, since it's essentially full manual control.

Guys, i have a question - I. See treads about air suspension faults all over the forum but on other hand those who does not have issues dont say anything to countrweight, is air suspension really really problematic?

:iagree:

I've taken the time to learn the various functions and so forth over time just out of interest.

I have had 1 suspension problem in 8 years. $65 height sensor. I personally don't consider that as problematic, so there's your counter.

The reason this comes up is because absent the time, resources, and desire to understand and deal with problems, the owner is otherwise at the mercy of diagnostic techs. Those who have good ones do fine. Those who don't spend money chasing causes and solutions via parts and labor.

The only actual part/assy tbat I would consider somewhat pricey is the compressor unit.

@ MrQ4.8is. Could you please confirm you have four wheel air suspension? Do you have any error lights on your instrument cluster? Have you read any fault codes (yet)? Front left corner is high, would you believe that the right front corner is at a normal height - as well as the rear corners? Have you checked the front suspension for damage - I am thinking the height sensors and the links from them to the struts?

All of the suggestions given previously are spot on - you need any of the various bits of software to read your car's code (been there, done that, it works and eliminates troubleshooting). The compressor is unlikely as your problem is specific to one corner, hence height sensor related or the air strut yourself.

Low risk and moderate expense to replace the height sensor. My X5 (rear air only) gave me a dash light. Plug in INPA and it told me the specific height sensor to replace (no guessing about air springs, compressor, leaky lines, etc). Useful technology, you simply use the tool that works with it.

Sorry about the delay in reply, been a little bit busy but thanks for the response, appreciated.

I have a 2004 X5 4.8is it has the four wheel height adjustment. The instrument panel reads up with suspension inactive fault message.

I've noticed the front left corner sits high looking at it I'd say height is at it's peak and the front right is high but not high as the left front, due to this (I think) the car is leaning down at the rear but looks to be very even on each of the rear corners.

The error codes read after resting the faults and driving the car around until the suspension inactive came up on the instrument panel by the way this was within 5 miles, using a "Snap-On" diagnostics computer the faults that came up after are;

Anti lock brakes - 5F1E Variant code info (ABS/ASC/DSC) - 5DD7 Height invalid (EHC error air suspension).
Air suspension - 80 Front activity plausibility.
Instrument panel - BD Electronic brake balance (EBV).

Cleared the faults drove a round this time got to about 30 miles before inactive suspension came up on the instrument panel. This time a different diagnostic computer was used "Auto-Boss" and faults list was;

NAME: ABS/ASC/DSC (Dynamic Stability Control)
VALUE: 1 Fault - 5DD7 - EHC Ride-height control, ride heights,invalid.

NAME: EHC Electronic Height Control
VALUE: 1 Fault - 80 - Activity plausibility front right.

NAME: ZKE/GM (Central body electronics/GM base module)
VALUE: 2 Faults -
1 - Fuse or lead for load circuit 1
2 - Fuse or lead for load circuit 2.

NAME: AHL Adaptive directional headlights
VALUE: 1 Fault - 01 - Communication with stepper motor controller 1 disturbed.

NAME: BM/MIR (On-board monitor/Multi Information Radio)
VALUE: 2 Faults -
1 - Control unit reset
3 - PL line:short circuit to ground.

NAME: SMF/SM/SLM (Seat memory,driver
VALUE: 1 Fault - 12 - Steering column,radial:short circuit.

Sorry for the essay, will try the above suggestions and very grateful for the suggestions and replies, in the mean time any of the above mean anything to anyone please let me know.

Regards MrQ4.8is.

Mr Q

Sorry about the delay in reply, been a little bit busy but thanks for the response, appreciated.

I have a 2004 X5 4.8is it has the four wheel height adjustment. The instrument panel reads up with suspension inactive fault message.

I've noticed the front left corner sits high looking at it I'd say height is at it's peak and the front right is high but not high as the left front, due to this (I think) the car is leaning down at the rear but looks to be very even on each of the rear corners.

The error codes read after resting the faults and driving the car around until the suspension inactive came up on the instrument panel by the way this was within 5 miles, using a "Snap-On" diagnostics computer the faults that came up after are;

Anti lock brakes - 5F1E Variant code info (ABS/ASC/DSC) - 5DD7 Height invalid (EHC error air suspension).
Air suspension - 80 Front activity plausibility.
Instrument panel - BD Electronic brake balance (EBV).

Cleared the faults drove a round this time got to about 30 miles before inactive suspension came up on the instrument panel. This time a different diagnostic computer was used "Auto-Boss" and faults list was;

NAME: ABS/ASC/DSC (Dynamic Stability Control)
VALUE: 1 Fault - 5DD7 - EHC Ride-height control, ride heights,invalid.

NAME: EHC Electronic Height Control
VALUE: 1 Fault - 80 - Activity plausibility front right.

NAME: ZKE/GM (Central body electronics/GM base module)
VALUE: 2 Faults -
1 - Fuse or lead for load circuit 1
2 - Fuse or lead for load circuit 2.

NAME: AHL Adaptive directional headlights
VALUE: 1 Fault - 01 - Communication with stepper motor controller 1 disturbed.

NAME: BM/MIR (On-board monitor/Multi Information Radio)
VALUE: 2 Faults -
1 - Control unit reset
3 - PL line:short circuit to ground.

NAME: SMF/SM/SLM (Seat memory,driver
VALUE: 1 Fault - 12 - Steering column,radial:short circuit.

Sorry for the essay, will try the above suggestions and very grateful for any suggestions.

Regards MrQ4.8is.
Mr Q

Mr Q

Whats an INPA.

Mr Q