Advice on fitting reversing sensors please?

[dvisor]

I've just got hold of a set of 4 ultrasonic rear parking sensors with wireless display. Apart from getting the wrong colour sensors they look like they'll do the job just fine.

The translated instructions are a little lacking (as usual), and before I go drilling any holes in my rear bumper, I want to be sure I get it right. I've never had parking sensors on any of my cars before, so I'm not too sure how they work.

From the instructions, it looks like the outer sensor should be spaced 0.3-0.4m from the next sensor. OK, that's fine, but how far should the outer sensor be from the end of the bumper? I'm probably being overly precise here, but better safe than sorry.

Also, the bit that concerns me is that I have a towbar fitted. Is this likely to be detected by the two inner sensors? If so, how far from the towball should the two inner sensors be positioned?

And finally! I'm assuming that if I fit a Bak-Rak to the towball, it will set the sensors off?

Thanks

[mikeonb4c]

I've just got hold of a set of 4 ultrasonic rear parking sensors with wireless display. Apart from getting the wrong colour sensors they look like they'll do the job just fine.

The translated instructions are a little lacking (as usual), and before I go drilling any holes in my rear bumper, I want to be sure I get it right. I've never had parking sensors on any of my cars before, so I'm not too sure how they work.

From the instructions, it looks like the outer sensor should be spaced 0.3-0.4m from the next sensor. OK, that's fine, but how far should the outer sensor be from the end of the bumper? I'm probably being overly precise here, but better safe than sorry.

Also, the bit that concerns me is that I have a towbar fitted. Is this likely to be detected by the two inner sensors? If so, how far from the towball should the two inner sensors be positioned?

And finally! I'm assuming that if I fit a Bak-Rak to the towball, it will set the sensors off?

Thanks

Although I've not got round to fitting the kit I bought (2yrs on!) I bought a 2 sensor kit as I read that there was no point fitting sensors anywhere near the towbar. I can't recall if this was because I have a towbar mounted step too, or just becuase of the towbar. So you are right to be asking. Hopefully someone else on here will know (or Google it - its amazing what comes back from that!).

If I ever mount my sensors, I plan to have them on the beginning of the curve of the bump side wraparound. The idea is to give good coverage of the blind spot caused by the rear pillar and that so often is the cause of grief.

[dvisor]

Thanks Mike - that makes sense. Maybe I'll just fit the two outside ones first (I'm also going to fit a step to the towbar when I can get to Towsure to buy one). I can always fit the other two sensors at a later date if I feel it's necessary.

[g8dhe]

Our factory fitted ones don't have any problem with the towbar - provided we aren't towing anything They are fitted about a foot either side of the towbar itself. If the rear corner ones are too far round the curve of the bumber you will end up sensing other vehicles to either side when parking which can mask other items until you get closer to them then the object beside you which is not a good idea.

[mikeonb4c]

Our factory fitted ones don't have any problem with the towbar - provided we aren't towing anything They are fitted about a foot either side of the towbar itself. If the rear corner ones are too far round the curve of the bumber you will end up sensing other vehicles to either side when parking which can mask other items until you get closer to them then the object beside you which is not a good idea.

Thats just one of the reasons I've put off fitting mine. I'm aware of that risk and don't want to drill and then found I've done it wrong. But I suspect there is an optimum position - one that will do what I require without going off when I'd rather it didn't. If I ever get round to it, I plan to tape the sensors to various positions on the bumper (or somesuch) and do some experiments. It may be the best place is well outboard, but still fully on the rear facing section (the theory also being that - in all seriousness really - I have a rear step to detect obstacles in the middle section )

[g8dhe]

How many have you got ? For the rear the factory ones have four fitted, two on the outer edges just on the curved section and two looking straight back, I've actually arranged for my two rear facing ones to be extended onto our back box when fitted, but you don't want to have the two rear facing ones too far apart either as otherwise you may miss seeing (hearing!) that post smack in the middle! Ours are also tilted up a little in the mount to avoid reflections from the road surface.

[crazy uncle gray g]

if your looking for a bit help, try google images just type in reversing sensors and you'll see loads of rear bumpers

[dvisor]

Well, my family are looking at me as if I've finally flipped. I've mocked up a rear bumper in my living room using a sheet of hardboard and the 4 sensors each spaced 40cm apart . Its difficult to get an accurate reading, but I reckon the towball can extend 20cm beyond the bumper between sensors B & C before it triggers the alarm. Spacing sensors B&C at 60cm apart, and A&B and C&D at 35 cm apart should give a little leeway and still give good coverage. That sounds pretty much how Geoff's are spaced.

The instructions say to place the sensors 50-80cm above ground, but the middle of the bumper is around 44cm off ground. This doesn't seem to be a problem though. I'm not getting any false readings at 45cm.

I think I am now certifiably insane. Hmmm, how do I rig up a mock towbar step?

[crazy uncle gray g]

Well, my family are looking at me as if I've finally flipped.
I think I am now certifiably insane. Hmmm, how do I rig up a mock towbar step?

I think they may be right
I suggest you sit back have a slurp of Scrumpy and get that drill out in the morning

[g8dhe]

The instructions say to place the sensors 50-80cm above ground, but the middle of the bumper is around 44cm off ground. This doesn't seem to be a problem though. I'm not getting any false readings at 45cm.

Wait till you pass over that pot hole in the road and the reflection from the back edge sets the alarm off, I reckon you need to make a little hard edged pot hole in the living room floor just to check this out

[dvisor]

I think they may be right
I suggest you sit back have a slurp of Scrumpy and get that drill out in the morning

That's what drove me this way in the first place!

The instructions say to place the sensors 50-80cm above ground, but the middle of the bumper is around 44cm off ground. This doesn't seem to be a problem though. I'm not getting any false readings at 45cm.

Wait till you pass over that pot hole in the road and the reflection from the back edge sets the alarm off, I reckon you need to make a little hard edged pot hole in the living room floor just to check this out

Yeah, you're right. I'd better go and get my spade. How deep do you reckon it ought to be?

[g8dhe]

Down here there about 6 foot deep ... tell you what I'll go and jump in it

[dvisor]

I wonder if this is asking for trouble:



The control box just about fits inside the rear light cluster, but its wedged in pretty tight when the cluster is fitted. It means I can run the cables straight down behind the bumper to the sensors, and also connect it up to the reversing light. Advantages are that no cables are coming in underneath the vehicle, and I don't have to remove any trim etc to fix the control box behind the interior rear side panel. If I want to take it out for any maintenance or if I have to remove the bumper for any reason, again I don't need to remove the panels etc - only the light cluster.

[g8dhe]

Is the control box waterproof or at least not going to suffer if there is moisture around ?

[rita]

I wonder if this is asking for trouble:



The control box just about fits inside the rear light cluster, but its wedged in pretty tight when the cluster is fitted. It means I can run the cables straight down behind the bumper to the sensors, and also connect it up to the reversing light. Advantages are that no cables are coming in underneath the vehicle, and I don't have to remove any trim etc to fix the control box behind the interior rear side panel. If I want to take it out for any maintenance or if I have to remove the bumper for any reason, again I don't need to remove the panels etc - only the light cluster.

Hi,remove the tray thingy insde the van,feed the wires through the grommet for the rear light cluster,stick the box to the inside panel.If you ever need to get to the box its only a matter of removing one screw and the tray.