How To: Retrofit 407 rear parking sensors

[battlestar]

I liked the idea of having the visual aid for parking sensors on my 407 so since only the factory fitted ones support mfd output i decided to install them myself.

Scope of work varies depending on the already installed features in the car, and seems i had the worst variant to begin with, so in this how-to i will cover all of the required wiring, equipment and procedures.

Tools required:
- Crimp multitool
- 10mm wrench
- 16mm wrench
- 3mm drill bit for plastic
- 10mm drill bit for plastic
- 33mm hole saw (or 32mm in case you cant find it)
- Electric drill (low or variable speed one preferably)
- Curved file, fine toothed
- Rund file, small diameter, fine toothed
- Fine and coarse sandpaper (if you dont have files, like me)
- Measuring tape (or self adhesive measuring tape, wish i had that)

Parts required:
- 4x parking sensors (6590 88)
- 1x parking sensors brackets (7414 FW)
- 1x parking control unit (6590 L7)
- 1x parking sensors/plate harness (6528 R7)
- 1x mfd with pdc support (optional, requires sw 21 or higher)
- 1x switch block with pdc + alarm + central buttons (6554 FA)

Parts and materials for rear harness (71 AC):
- 1x 18 wire connector with lever (6541 H9)
- 6x connector crimps (6542 WY)
- 3x connector crimps (6541 E7)
- 1x spade crimp for grounding
- 4x 2.5m of 0.5mm2, two each of black and red (AWG 20)
- 2x 0.7m of 0.5mm2, both PE ground color, green-yellow (AWG 20)
- Felt tape (i got tesa one for 2EUR from local car shop)

Parts and materials for mid harness (46 HAB):
- 2x blade crimps (6541 G4)
- 2x 4m of 0.5mm2, one each of black and red (AWG 20)

Above are all required tools, parts and materials required to complete this project, grouped for better overview. So like i mentioned before, depending on the installed wiring in your car, you will be required to different amount of work. Use simple guide below to determine where in this how-to should you start. Also depending on weather you have ultrasonic alarm sensors and central locking, you might have to get different switch block w/o unnecessary buttons. What i did was, i got the switch block from 1007, and simply took the pcb and pdc button from it and fitted them instead of my pcb and placeholder button.

Where to start:

- Lift the boot mat to reveal spare wheel.
- Look for 2 metal screws protruding from chassis in lower right corner.
- Check for white 18 wire connector in vicinity of those screws and license plate lights interconnection.
- If its there, it shouldnt be connected to anything, and if it is connected, then you have PDC unit, and most probably the parking sensors, so you dont need to do this how-to.

If there is no white plug, you will need to do Step 1.

- Open boot and remove the left recess door to expose fuse box.
- Look for green plug on the side of it and disconnect it.
- Check for wires 1 and 2 on the female plug, leading to the passanger compartment.

If there is no wires 1 and 2, you will need to do Step 2.

Step 3 covers the installation of license plate harness with pdc wiring, which i am pretty sure is never included on cars without pdc. Same cannot be said for first 2 steps, thus they are conditional and last one is, lets say mandatory. In process of removing plastic panels around the car you might end up breaking few hog rings and plastic staples here and there, so its always a good idea to have few spares. Part numbers are 9341 PF (hog rings) and 7588 VX (plastic staples).

Wiring diagram:

[battlestar]

Step 1 - Wiring and installation of rear harness (71AR)

Removing the boot trim:

- Remove the boot trim and plastics
- Remove the spare wheel and tools

Making the PDC harness:

- Take the 4x 2.5m wires and 2x 0.7m wires.
- Crimp one side of each wire with one of 6x 6542WY connector crimps. (Pic 1.)
- Take 4x pieces of clear tape and 4x small pieces of paper
- On 2x of each papers write numbers 5 and 14.
- Now stick the same numbers on each end of first black wire, then the second black wire.
- We will use the numbers later on to identify which of the 2 black wires is which.



- Take the white 18 wire connector and remove the black wire holder (Part 2.).
- Take the wire holder and look for number markings on that define the wire positions (1-9,10-18).
- Insert wires in following order: (Pic 2.)

1. Short earth wires in 1 and 10.
2. Long red wires in 2 and 11.
3. Long black wires in 5 and 14, matching the numbers written on the tags.

- Using felt tape, tape together the first 12cm of wires from the wire holder side in circular motions.



- Take the harness to the car and connect the white plug to PDC ECU.
- Now try to follow the existing AR71 harness path all the way to rear fuse box with red and black cables.
- Red cables should be able to reach the gray connector in fuse box.
- Black cables should be able to reach the green connector next to fuse box.
- If the cables are too long (they shouldnt be) trim them to right length, in case you would cut off the part with number tag, replace number tag at the new end of the wire.
- Now try to follow the existing AR71 harness path to MC60 earth point beneath the right light cluster with green/yellow earth cables.
- Earth cables should be able to reach the earth point.
- If the cables are too long, trim them to the right length.

- Take the other side of black and red wires.
- Crimp each of the black wires with one of 3x 6541E7 connector crimps.
- Crimp the red wires together with single 6541E7 connector crimps. (Pic 4.)
- Crimp the earth wires together using single spade crimp.



- Hoist up the cables between two points and stretch them and fix in place.
- Using felt tape, tape together rest of the cables, starting from the point you taped up to last time, but this time excluding the earth wires.
- Tape the cables all the way, leaving about 30cm untaped at the other end.
- Tape the earth wires all the way up now on their own, leaving about 10cm untaped at the crimp end.

You should end up with something looking like this:



Pretty damn close to the real thing, right?
Note that i have removed the green plug from the car and already fitted it onto the harness.

Installing the rear harness:

- Take your freshly done harness to the car.
- Disconnect battery and undo the M10 bolt with a spanner.
- Connect the white connector to PDC ECU.
- Connect the blade crimp to earth point MC60.
- Remove the orange retainer clips from gray and green plugs at the fuse box.
- Insert the red wire crimp into gray fuse box plug in pin 4.
- Insert the black wire 5 into pin 2 on the green plug.
- Insert the black wire 14 into pin 1 on the green plug.
- Replace the orange retaining clips back onto green and gray plugs.
- Now that you are done wiring everything up, double check ther wiring by comparing to the wiring diagram above!
- Using 10cm long pieces of felt tape, affix the new harness to the existing AR71 harness at each strap that fixes the harness to the small bolts on the chassis.

Now that everything is connected and in its place, you can replace the plastic bits, trim and spare wheel. Work your way back from last step to replace boot trim.

Forum only allows 4 images per post, so last few steps include images in links when you click on the step itself.

[battlestar]

Step 2 - Wiring and installation of middle harness (HAB 46)

[battlestar]

Step 3 - Installation of pdc harness and sensors with drilling

[sterion75]

Your a master battlestar, that guide is up there with the best. I may do it myself...or it might be one job too far for me. Since getting all my jobs done with no hoist all at ground level I've developed sciatica, the pain is worse than keep opening my wallet for parts. Even so, now the hard work has been done for us it might be on. Nice little earner for you on weekends fitting sensors. Brad
Mmm very well set out like it a lot, but cant open the steps 1 2 3

[battlestar]

Thanks Sterion, i've put alot of effort into this. But i doubt there will be any candidates looking for retrofit. Steps 1,2 and 3 are still WIP, im writing it bit by bit instead of one huge post at one time.

[sterion75]

I can see why you've done it that way. Organising it into steps has taken a lot of time and planning. I find parking awkward, Its the only vehicle I've had where that's happened, so the value of the system is obvious. I am going to evaluate the possibility of doing this, with a check in the boot first. Have you worked out the costs involved if all the parts are needed?

[battlestar]

Yep, thats why i even bothered doing this. and i must admit, parking now is a treat, much much easier.

Costs are something like this:

- PDC ECU ~50EUR
- PDC Sensors ~80EUR (i got mine for 120EUR with support brackets)
- PDC Brackets ~40EUR (from dealer, need to be painted)
- Rear plate harness with PDC Sensors wiring ~30EUR
- PDC On/Off button ~10EUR
- materials ~20EUR

~230EUR total, most of those things you can find even cheaper at local scrapyard, i got mine all of ebay.

Which i think makes this even cheaper than when factory installed, no?

[bogdan20]

after an accident I had to change rear bumper and I changed it to one of dismantling which already had parking sensors, and the module but I think the car is not wired properly, so I think I need your item step 3. when the step 3 will be ready. thank you in advance

[battlestar]

Hi bogdan, ill probably get to it tomorow. Are you sure you have PDC ecu? its not on the rear bumper, but inside of the boot, under the mat, next to the spare wheel.