Originally Posted by someguywithajag

Did anyone ever find a way to have those ring gears made? I would like to repair the powerfold function on mine...

Originally Posted by bballarin

If your powerfold mirror mechanism breaks, you used to have 2 options:

• Buy a new powerfold frame for around £370
• Buy a used powerfold frame anywhere from 50 to £100+

Do not trust fleebay guys claiming to sell refurbished powerfold mirrors (refurbished = working like new according fleebay terms). In the best case, these mirror frames have just been cleaned and that's it. On this video you can see the behavior of a supposedly refurbished right side powerfold frame just failing out of the box (received from fleebay member blackcountry jaguar).
video

So I decided to go a third path and rebuild my powerfold mechanism myself. It is not cheap but still much cheaper than buying a new one. Futhermore, I discovered and cured the weak point of the design, I now have a powerfold mechanism which I believe will last for life.






















First of all the disassembly of the pivot. I will focus only on the difficulties:

• separate the 12 wires from the connector. Here is how I do it. While I am pushing on the needle towards the right with my index, I pull the corresponding wire at the back of the connector.

• Here is the wiring for reassembly:
• 
• Then you need to tear down the 12 wire harness by removing one by one all the wires from the sheath. This is made difficult by the fact that the wires are glued inside the sheath with some silicon to prevent water ingress. So you first need to extract the silicon with a srew driver without damaging the wires or the sheath. Note that you could also cut the sheath and replace it with a new one, but I have been able to save them every time.
• Next is time to extract all the wires from the sleeve (part #15 below) that goes across the pivot.
• Now you need to remove the L shape plastic covering the electrical engine and primary gear set. That gives you access to the 2 electrical engine contacts that need to be unsoldered.
• Turning the pivot upside down, you can now remove the last 2 wires coming from the electrical engine and you are ready to remove the stop washer from the end of the sleeve.
• It is now time to remove the microswitch:

You can see 2 diodes that very well could be burnt. If that is the case they need to be replaced by rectifier diode able to withstand 1A. I have been able to measure peak currents close to 1A when the mirror reaches final position.

For those who want to understand this twin microswitch, first you need to understand that the power fold electical motor is controlled by the car body processor with just 2 wires. The car body processor applies 12V in the 2 wires for a duration longer than the time required for the mirror to reach position. In order the prevent burning the electrical motor or breaking gears, the twin microswitch shown below opens the circuit and closes another circuit in order to be ready for the inverse movement when the body processor will apply 12V with opposite polarity. It is key yo understand that the 2 pieces of the microswitch shown below stay still during all the time while the mirror is moving. The 2 pieces of the microswitch only slide, one with respect to the other, when the mirror stops at its final position.







A complete unfold/fold Cycle is depicted below (sorry there is a bit of french left, so you know where I am coming from ;-))















Now the last point consists in disassembling the gear set and the 3 frictions. This is done by uncrimping the black plastic gearset cover on top of the pivot (part #18 below) and removing a big stop washer (part 1 below, be carreful it is under load of 2 big springs and there are a lot of shims and friction rings ready to fly around). Once done you are in front of this:

•  
  • 1 stop washer
  • 2 friction ring
  • 3 thin spring, large diameter
  • 4 thick spring, small diameter
  • 5 Ring with stops for fully open mirror
  • 6 mobile part of the pivot
  • 7 friction ring white
  • 8 friction ring black
  • 9 fixed part of the pivot
  • 10 friction ring white
  • 11 friction ring black
  • 12 frcition ring white (internal splines)
  • 13 friction ring black
  • 14 shaft
  • 15 sleeve
  • 16 engine cover
  • 17 engine and 1st level gear set
  • 18 fixed ring gear
  • 19 planet gear carrier
  • 20 sun gear
  • 21 mobile ring gear
  • 22 fixed ring of the microswitch
  • 23 moving ring of the microswitch
  • 24 stop washer
  • 25 protection sleeve

• There are 3 frictions with different sliding torque threshold that are in this order, from the weakest, to the strongest friction
  • for moderate torque (during electrically operated mirror movement), only parts #6 to #9 are sliding
  • 
  • For sligly stronger torque (required to operate the microswitch at the end of the movement, or mirror folded by hand) parts #9 to #14 are sliding.
  • 
  • Eventually, for a even stronger torque (mirror opening past the normal position towards the front of the car, due to shock or microswitch not working) parts #5 and #9 are sliding.
  • 
• It is important that all the 3 frictions slides according their specified torque threshold so they should be disassembled, cleaned, and greased with silicon grease (plastic parts).

Here is a video showing how operate the first 2 frictions:

IMGA0923 - YouTube

• Last but not least, part 21 (mobile ring gear) is almost always damaged and is clearly the weakest point of the gear set. The central part of piece 21 is made of aluminium (the 2 spurs would break if made of plastic due to strong torque to be transmited to the shaft). But the external ring is made of plastic, look at how badly the gears can be damaged:

With such damaged gears, at best the mirror only moves to position but is not able to operate the microswitch (noisy cracking gears at the end of the movement), or even worse, it is not able to move the mirror at all (gear noise all the time). This is only going to deteriorate rapidly.

I decided to have a ring gear rebuilt in stainless steel.

Here is the manufacturing process involving electro-erosion:

- Step 1, build the outline with a lathe
- Step 2, build a copper electrode having the required gear shape with wire-cut method
- Step 3, press the electrode in the stainless still ring (electro erosion)
- Step 4, Cut the spurs with wire_cut method








Here is a rebuilt powerfold pivot with the stainless still ring gear, new diodes and silicon greased frictions: video

I can have stainless steel gears built on request and could consider rebuilding pivots if this job is too scary for you.

Cheers,

Bruno

Originally Posted by John Parker

This is a brilliant article but I'm afraid too clever for me however it certainly guided me in the correct direction and I would have been lost without the information.I did dismantle a 1999 XJR a few years ago so proceeded with the information to hand to dismantle the LH mirror assembly from that vehicle. The actual mounting bases were different and we had to remove the door electrical plug from the old XJR unit so that it would fit inside the body with its narrower tunnel. I affraid we gave up trying to remove the 12 pins inside the plastic connector after about two hours and just cut all 12 wires. The whole motor assembly and wiring was fitted into my XKR mirror shell.
Assembling the wiring through the mounting base was a nightmare but eventually it was completed. All 24 wiring ends were tinned with solder, heat shrink tubing fitted to the long ends of the wires. Each wire was carefully soldered together with its corresponding colour. After that each shrink tubing was pulled across the joint and all 12 wires heated with the wifes hair dryer. I can report that I now have twins, mirrors that is ;that work just as they should.Thanks to all this forums supporters and the info available on the internet. I hope I never have to do this job again. Cheers John

Originally Posted by bballarin

Hi,

first of all, almost 9 years after my power fold mirrors were rebuilt, this quick message to confirm they are still working very reliably.

Today, a member of the same machine shop forum where I found the guy who built my 2 stainless steel rings (part 21) contacted to say he can do the same.

He proposes 2 methods:
- Method 1: the same electro-erosion method that is described above
- Method 2: build the ring in 2 parts (wire-cut), welded together with micro Laser beam

If anyone is interested, please let me know the quantities so i can request a first quote.

I propose the following contribution to validate the solution:
- I have a spare power fold mirror, I will send the gear set to the machine shop so that they can take measurments and build a new prototype of part 21
- I will ask to have the prototype shipped to me so that I can reassemble a complete pivot and test it like I show on the video at the very end of post #1 above
- I'll give green light for the machine shop to build identical parts to whoever of you ask more items to him

Cheers,

Bruno

Originally Posted by bballarin

..... almost 9 years after my power fold mirrors were rebuilt, this quick message to confirm they are still working very reliably.....