Intermittent C1889 Error - Suspension Fault / Car too Low

[Lordgaz]

Hi All

I am looking for some advice re: a fault which popped up from nowhere - I have returned from a 50 mile drive on Sunday - Monday morning I get a message showing suspension fault, car too low - I got out and had a look around the car, and the height seemed fine - (if anything, a little high at the front) - Code read on iCarsoft as C1889 - Front left height sensor - open circuit/short circuit to ground.
I drove the car for a few miles, and the suspension felt hard - then the errors stopped showing on the dash - felt better, then they returned, sometimes flickering on and off - Wiring issue do you think?
If so, I would like to test the wiring loom from the left front height sensor - Does this cable/loom go from the front wheel area to the suspension control module directly? Does anyone have any advice on the best way to access the control module?

Many thanks
G

[BrianG]

If you have an early model it will have two sensors at the front, whereas later models only have one fitted and I believe a shorting link for the other position. Apart from wiring problems it's worth checking that the sensor, actuating arm and mounting bracket are still correctly attached as any of these can give errors should it come loose. See earlier posts in the X350 pages by Mike Kennedy on this topic.

[J44EAG]

Brian is absolutely correct.

The first cars had both front sensor units operating to level the car. Later examples from about 2004 used just the near side unit actively working with the off side unit just being there to complete a circuit.

It is worth looking to see if both sensors are still attached to the front suspension arms and that they are not falling apart. The fixing springs can corrode, break or otherwise detach. My near side sensor is cable tied to the arm as a repair. New spring clips are not available without buying a complete new unit. Mine got knocked off on a flat bed recovery truck ramp. Hence the economy repair. It has now been in place for three years without further issue.

Harshness of the suspension can be caused by an issue with the connector or the air spring itself. The connector is on the top of each suspension damper centre. Remove the plastic cover on the top of the damper mounts to access. The damping is controlled between hard and soft by some sort of gadgetry atop the air spring.

Mike

[Lordgaz]

Brian is absolutely correct.

The first cars had both front sensor units operating to level the car. Later examples from about 2004 used just the near side unit actively working with the off side unit just being there to complete a circuit.

It is worth looking to see if both sensors are still attached to the front suspension arms and that they are not falling apart. The fixing springs can corrode, break or otherwise detach. My near side sensor is cable tied to the arm as a repair. New spring clips are not available without buying a complete new unit. Mine got knocked off on a flat bed recovery truck ramp. Hence the economy repair. It has now been in place for three years without further issue.

Harshness of the suspension can be caused by an issue with the connector or the air spring itself. The connector is on the top of each suspension damper centre. Remove the plastic cover on the top of the damper mounts to access. The damping is controlled between hard and soft by some sort of gadgetry atop the air spring.

Mike

Hi All - thanks for the input. I have resolved this now. I was geared up for some serious continuity testing (extra long leads and thin probes bought) but once the wheel was off, it was pretty clear what the issue was - broken wire - Soldered/Heat Shrinked and back to normal!
I found this below PDF which was extremely helpful should the issue been less apparent.

http://jagrepair.com/images/Electrical/ ... 0Guide.pdf

[J44EAG]

Well done. Nice to have a happy ending.

Mike