Apologies if there are already threads on this, I tried "Advanced Search" but didn't find any.

My parking sensors (front and rear) have just stopped working. It might be relevant that we are in a period of heavy rain.

There is one long beep when you first start the car; after that, no beeps.

I had a look in "menu" but don't see any way to turn them on or off.

Any ideas?

TIA

 

Don't you have a switch o button on the sunroof control panel to turn them off?

 

Do I?

I'd better find my owners manual and look it up.

 

You will have a parking sensor button on the overhead console. The button has a large P on it.

Thanks,

Chris

 

Thanks for the advice. I have found the "P" button and also my owners guide.

The little red light comes on, and the long beep sounds, when I put the car in gear and the parking aids (should) come on. The button is unable to make the system work. The light and beep indicates that there is a problem in the parking aid system

Don't know what the cause is.

It will have to go to the mender.

 

Seems odd that both front and rear fail at the same time. Lots of instances in this forum where either rear or front fail but not both.

If it were me I would look at the control module in the trunk. Easily replaced and not expensive if bought used on Ebay.

I hate to think what a dealer would charge.

 

No dealer for me!

Yes, it's quite likely a wiring or control module fault.

Might be wiring around the bumper sensors, as they are exposed to wet and grit.

Interesting that there is "fault detection" circuitry.

One of these, you think? Is it by the spare wheel, or the DVD player?




https://www.ebay.co.uk/itm/REVERSING...oAAOSwJMBdEzHU

 

It is likely just a failed parking sensor. If one sensor fails, front or rear, the whole system goes into an error state and lights up the red error light next to the "P" switch in the console. A search for "parking sensor" (use the quotes in your search) will bring up some existing threads on how to check the sensors.

Dave

 

I do not think so.

I had a front sensor fail and the rear were still working.

 

My 2005 Super V8 has the same problem as the original poster. But mine works intermittently. So just wait a week or 2 and viola!

LOL. While I like everything to work, I have bigger issues, so this one waits.

Mike D.

 

My experience with a front sensor failure twice now is neither reverse or forward alerts happen after the error tone. Also, from the 2008 owner's manual, "If the system has a fault when engaging reverse gear or turning on the ignition, then a single, three second tone will be heard (only once per ignition cycle) and, if fitted, the switch lamp will come on. The system is automatically disabled when a fault is detected." Maybe this is different between X350 and X358 vehicles, but that has been my experience.

Dave

 

My rear sensors stopped working for several months but the fronts continued to work fine. It threw some codes for the rear sensors and I was unable to reset them. I didn't do anything about it and then one day, the rear sensors started working again. I can't explain it. If you have a code reader, check and see if there are any codes for sensors not working. Also, what model year is it?

 

That is a controller for 4 sensors in the front and 4 in the rear hence the "8Ch" designation.

If it were just the rear only it would have a "4Ch" designation.

 

Yes, that's the behaviour I'm getting.

I remember having a sensor changed once before (I think it had to be sprayed to match the bumper colour) but I don't remember if I got the long beep.

 

I too get this problem. Sometimes the parking sensors work and sometimes they don't. At the moment I just switch them off until I can get a chance to fix the problem. I think my problem is caused by a faulty sensor as the problem is more noticeable in wet weather.

 

I'm willing to bet there is a big group out there who have experienced this. They work well... when they work. But the system is sensitive to failures - from sensors that fail too often, dirty/wet sensors and wiring harness for the system failures. I think it is unusual for the module to fail. I have a truly weird scenario. My system (Front/Rear) ONLY works when the ambient temps are 75 degrees plus. Worked ALL summer like a charm in North Carolina except for a few cool evenings. Now its getting cooler and it will quit all winter and stay broken consistent with temps until the spring. As soon as it goes above 75 degrees it all works again. Cool days - long beep, no park assist.

I bought an 8 Channel module in hopes it would work but did not expect much. Good thing because I didn't get much. Same behavior. Lately it works ONLY on the warm fall days. I HATE to be without it in a LWB X350 with tinted glass. My assumption is multiple sensors or the wiring harness has a sketchy section that expands and softens when its warm, allowing current. As soon as it gets below 75 degrees, the harness stiffens and breaks contact or shorts two wires.

Sadly I have spare sensors - I bought 4 90 degree ones that are said to work in an position, where straight connector sensors only fit the center bumper in front. and 90 degree ones are for the outer ones. But my splash panel bolts are rusted on solid. Cutting them off won't be TOO bad. I am just not fond of pulling the bumper covers. They fit perfectly to the bodywork and join the front fenders and quarter panels without and misfiring where they clip on just in front of the front wheels and just behind the rear wheels. Can someone tell me if getting the bumper covers clipped back on perfectly is challenging? I will be miserable if the clips fail, break or just don't allow a perfect re-attachment. Also, if I pull the covers, can anyone quote a part number for the wiring harness?

Better still, does anyone have shots of the harness and where it goes through to the bumper? I have had the module out/replaced but cannot see much of the harness.

 

John

I have had the front bumper off a couple of times and its gone back on perfectly.
Once all the rusty fixings are removed you need to tug slightly downwards at each side, their are plastic tangs which hold it in place. I haven't heard of these breaking off.
Have a mate help you to support it and put a cloth on the ground so you can lay the bumper down in front of the car without it getting scratched.
The bumper wiring harness connector in my 2003 RHD xjr (which includes wiring to the parking sensors and the front fog lights) is in front of the right hand wheel (looking towards the front of the car) behind the wheel arch lining.
The wiring harness is clipped to the rear of the bumper. If you are removing the parking sensors have a good look before you dive in as the clips that hold them in place are easily broken (ask me how I know!)

 

 

My rear left sensor was intermittently working and so I tasked myself to replace it with a second hand unit.
Firstly I removed the hard plastic trim inside the boot (trunk) and plied away the liner. Since it was only a corner sensor I did not unbolt the whole rear bumper, only the left side which gave me plenty of room to remove the old and in with the new. I thought the corner sensors were 90° ones and not like the straight version that I pulled out but nether the less it still connected and is working properly now.

2 types. Straight and 90°. I bought them second hand in my car's colour but if new you would have to paint them.

Removed the hard plastic cover trim and pulled away the lining

I only removed the bolts in green.

The faulty sensor in the corner which was not a 90° one. Just slowly prise up the clip and full out as it maybe brittle.

 

Good to know that they will interchange with one another