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Aftermarket reversing sensor fitment

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Nathanio
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Posts: 31
Joined: Sat Oct 30, 2021 9:28 am

Aftermarket reversing sensor fitment

Post by Nathanio » Sun Jan 16, 2022 3:56 pm

Afternoon all,

My wife asked me to fit rear sensors to the car as she's got used to them on her cars and as such listens out for them by instinct. She's also not used to parking a car where you're more rearward than in a normal car. So £50 on a good sensor kit seems like cheap insurance.

First thing was to fit the sounder and control box. Sounder is over my shoulder in the vent behind the drivers seat. I've then routed it under the rear carpet and brought it out near the rear left light cluster. I've attached the control box next to the rear arch vent.

I then found the reversing wire in the cluster using a multimeter (blue and yellow) and used a solder sleeve to join them with the power for the control box. Used an M6 ring terminal on the ground and went onto one of the cluster securing bolts
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cable-gnd.jpg
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Next I removed the bumper (which I won't cover here as it's covered else where), but found that the plastic rivets are a pig to remove. I used a pair of these blue pliers to do it with the wheels in situ
pliers.jpg
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Bumper off
bumper-off.jpg
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I also had the centre rear bolts head give up with minimal torque applied. Something to sort another day.

On the back of the bumper is some squares to show where you need to put the sensors
bumper-square.jpg
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I then marked the centre by drawing across each corner
bumper-cutmark.jpg
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I then used a small 1mm drill bit to pilot hold through. Then cleaned the bumper outside and attached masking tape.

I then used the included 21mm hole saw to cut the holes. Leave the drill on low and let it do the work. I did need to stop and clean the hole saw of plastic build up. Slow and steady is the goal here.
bumper-drill1.jpg
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Clean up with a deburring tool

I found that my bumper has had filler for a low speed incident in the past
bumper-drill2.jpg
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Run the wiring across the back of the bumper in the clips that hold the plate lights. Cut the grommet and pass the cables through. Seal off with some headlight sealant.

I cable tied the excess to the top of the crash bar.

Put the bumper back on and leave clipped at the top but do not fit any fasteners. Attached sensors to cables and now test to make sure that all work.
bumper-sensor.jpg
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Then reverse the removal to reinstall and stand back and admire.
bumper-done.jpg
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These are classed as grey but are a subtle shade of grey lighter. Annoying but not the end of the world. Can always get them colour coded at a later date.

I did replace the plastic rivet centre pin as I'd chewed them up getting them out. I tried some alternative screwed in ones, but they wouldn't sit in as securely.

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colb
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Location: Newport, South Wales UK

Aftermarket reversing sensor fitment

Post by colb » Mon Jan 17, 2022 5:54 pm

My car already had front and back sensors fitted when I got it with the control box in the boot next to the battery. The sensor wires from the front were just cable tied together along the underside of the car which looks untidy, will be sleeving them into some split plastic conduit when the weather gets warmer and tidy up the run from front to back. I fitted sensors on the rear of my previous daily car and used split conduit to sleeve the rear sensor wires back into the boot to the control box rather than just bunch them together, makes a more tidy job using the conduit.
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