P38A Height sensor

Anyone had a height sensor apart to clean? If so how do they come apart?
I have a spare that I have done a resistance test on and it is ok through about 75% of rotation an then goes flat. I was hoping to see if I could clean the inner track. Visibly there doesnt seem to be a way in......

Assuming they work the same way as an L322 then the track is probably worn out so not just a matter of cleaning.
I hacksawed my way into this L322 one

Hi just found this thread, advice seems to be don’t take it apart if you can’t seal it up again.
https://www.landyzone.co.uk/land-rover/p38-eas-rises-automatically.150658/

Good luck, Tricky

backinblack said:

Assuming they work the same way as an L322 then the track is probably worn out so not just a matter of cleaning.
I hacksawed my way into this L322 one

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I guess you couldn’t use it again?

backinblack said:

Assuming they work the same way as an L322 then the track is probably worn out so not just a matter of cleaning.
I hacksawed my way into this L322 one

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Don't think they are design to be split, especially where they are located

Tricky of York said:

I guess you couldn’t use it again?

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I wouldn't even try. Don't think it was faulty in the first place, after 2 new sensors it turned out to be damage in the loom over the wheel arch.

I took a P38 1 apart years ago and managed to revive it to at least work while the new 1 came (and I went offshore again)
It worked but is not a permeant fix, they are sealed and you have to be carful when getting into it then seal with silicone.

Not worth the effort to be honest for you guys, My situation was diff at the time and needs musted at the time.

Bin it

J

backinblack said:

I wouldn't even try. Don't think it was faulty in the first place, after 2 new sensors it turned out to be damage in the loom over the wheel arch.

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Not a surprise to be fair. I’m fast coming to the belief that many automotive issues are caused or associated with the stupidly complexed wiring looms. It took me two days to sort the fan motor control on the family Citroen, what a mess.
Tricky

@Henry_b posted some photos,try a search

Tricky of York said:

Not a surprise to be fair. I’m fast coming to the belief that many automotive issues are caused or associated with the stupidly complexed wiring looms. It took me two days to sort the fan motor control on the family Citroen, what a mess.
Tricky

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My issues were caused by stupidity of the dick that thought twisting wires together and taping them up was a good idea.

All they are is a potentiometer used as a potential divider, they can be taken apart however you can't get them back together..

Usually the track wears out or water gets past the seal and ruins it.

Best replace it..

To test them you need a multimeter.

there are three pins, the 2 outer ones are the track and the centre one is the sweeper, with the meter on the resistance setting touch the leads to both outer pins, if you get an open circuit then junk it, you should get a resistance of around 2ohms if its ok

next up put one lead on the centre pin and another on one of the outer pins, then slowly run the sensor arm through its travel looking for either spikes in the resistance reading or open circuits at points over the track if you get either then the sensor is junk..

I have taken one apart, they are not a serviceable item. There is a double track one giving a rising resistance and the other a falling resistance as the shaft is turned. This is to reduce the sensitivity.
The one I took apart only caused trouble when the road was wet. turned out that the O ring sealing the shaft had failed so letting water in.
I think I have photo's if you want to see the inside.