Parking sensors

[3hcp]

Just noticed my rear parking sensors on the spyder aren’t working, before I delve too deep are there any obvious or reoccurring problems with them or a volume control?

 

[midlifecrisis]

Just noticed my rear parking sensors on the spyder aren’t working, before I delve too deep are there any obvious or reoccurring problems with them or a volume control?

You can hear them clicking, with the engine OFF (important!), put the car in reverse and put your ear against them, you should be able to hear a high pitched click. Use a person under 30 as their hearing is much better at higher frequencies (fact!)

 

[3hcp]

Think I have found the problem, there’s a little bit of play in the lever when in reverse, just enough to release the micro switch in the second photo. Is there anything a layman like me can do to tighten it up?
I have a lift.

 

[midlifecrisis]

Think I have found the problem, there’s a little bit of play in the lever when in reverse, just enough to release the micro switch in the second photo. Is there anything a layman like me can do to tighten it up?
I have a lift.

It's hard to tell from your photos and I've lost my recency on 4200s but you should be able to *gently* move the microswitch. Either they are screws that hold it in place that can be loosened, repostion the switch then retighten, or bend the metal arm gently so that it engages (which I cannot see).
The microswitch will just be a closed contact which passes a signal to the 'brain' to engage the reversing system and it looks like the plug on the right with the blue and black wires are where you can disconnect it if required. They do wear out as they are mechanical and it is 'just a switch' which, if Maplins were around you could pop down to and find a suitable replacement...a motor factor might have similar.

 

[MarkMas]

Would it be the

Think I have found the problem, there’s a little bit of play in the lever when in reverse, just enough to release the micro switch in the second photo. Is there anything a layman like me can do to tighten it up?
I have a lift.

Would it be the same microswitch that puts on the reversing lights (and maybe shows an 'R' in the dash?) - that would be a way of confirming that this is the problem, not just a sensor failure.

 

[3hcp]

the microswitch itself is fine and there's no adjustment, its the gear linkage that has some play whist in reverse that disengages the microswitch contact.