DiagBox / Lexia parking sensor volume

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la20
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Joined: 31 Jul 2022, 10:37

DiagBox / Lexia parking sensor volume

Post by la20 »

Hi
I have an issue with my C4 Picasso B78 (2014) in that the front n/s parking sensor works fine but has very low volume, (all the others work fine and volume is loud with radio volume dropping when they activate)

I have DiagBox 7.83 instaled on a virtual machine running on windows XP pro 32bit.

I have not used DiagBox before so am looking for some assistance in how to use it properly without breaking something else in the process lol. I have searched this forum and youtube but can not find anything specific to parking sensors on Diagbox

I have tried adjusting the volume on the radio whilst the parking sensor is sounding (close to a wall) but this made no difference.

Any help would be appriciated, Thanks
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GiveMeABreak
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Re: DiagBox / Lexia parking sensor volume

Post by GiveMeABreak »

The sensor volume is supposed change form left to right and in volume depending on the distance and location of an object. There's no setting in Diagbox I am aware of to change anything.

So in other words the sound emitted intensifies the nearer an object gets - this is by design.

There may be a setting to adjust the sound source level elsewhere with the diagnostic equipment, but it really should not need to be changed as they are pre-configured to work correctly.

Also be aware that the outside temperature can also affect the calculations made by the system when measuring distance, as the parking assistance ECU uses this data. So if it is an extremely hot day there may be a temporary glitch, but generally I've never heard of this being an issue before.
la20
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Re: DiagBox / Lexia parking sensor volume

Post by la20 »

Thanks Marc
The low volume is only on the one n/s front sensor, all the others are ok. Do you think it could be the sensor itself?
Thanks
Hell Razor5543
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Re: DiagBox / Lexia parking sensor volume

Post by Hell Razor5543 »

I wonder if something might be 'muffling' that sensor? What might be worth trying is to place an object in range of the suspect sensor, measure the distance, and then see where the parking assist system 'thinks' it is. Then do the same for the opposite sensor. If the parking assist system 'thinks' there is a difference then maybe the suspect sensor is slightly 'deaf'.
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GiveMeABreak
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Re: DiagBox / Lexia parking sensor volume

Post by GiveMeABreak »

la20 wrote:
31 Jul 2022, 18:10
Thanks Marc
The low volume is only on the one n/s front sensor, all the others are ok. Do you think it could be the sensor itself?
Thanks
So just to clarify the volume should increase when the detected object is nearer. So to test this you would need to move the vehicle in a clear open space with no obstacles near. Then apply the handbrake and get somebody to gradually walk towards the offside sensor slowly so you can hear the specific volume on that sensor as a benchmark. Then repeat slowly on the nearside sensor and see if the volume increases slightly as the person walks closer (up to a max. of 25- 30 CM which is the minimum detection zone).

If it's activating and detecting up to that distance and is doing its job, I would leave it alone as these are not cheap to replace and there's no guarantee it will be the sensor. The sensor volume won't be configurable individually in any case, so that won't help much.

Normally if the sensor is faulty the parking assistance ECU will flag a warning and deactivate the whole system whilst a fault is present.
la20
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Re: DiagBox / Lexia parking sensor volume

Post by la20 »

I have just got the wife to approach the car and the o/s sensor does not increase in volume as she walks closer to the car, the beeps just get closer together untill it is one continuous warning but volume stays the same. the display also works ok with lines showing green then red?
la20
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Re: DiagBox / Lexia parking sensor volume

Post by la20 »

I have just checked the front l/h lower door speaker in the car and it isnt working, so I think I have found the problem (hopefully) Thanks for your replys
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Re: DiagBox / Lexia parking sensor volume

Post by Hell Razor5543 »

la20 wrote:
31 Jul 2022, 19:07
I have just checked the front l/h lower door speaker in the car and it isnt working, so I think I have found the problem (hopefully) Thanks for your replies
That would explain it! :D
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GiveMeABreak
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Re: DiagBox / Lexia parking sensor volume

Post by GiveMeABreak »

That would of been my next check, but glad you have found it.