[OEM+] Honda Prelude - Automatic Passenger Window

[ZippiT]

Links to more modifications:

• [OEM+] Honda Prelude - Automatic Passenger Window
• [OEM+] Automatic Headlights
• [OEM+] Honda Prelude - One Touch Turn Signals
• [OEM+] Honda Prelude - Keyless Trunk/Boot Opener

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The following is a write up post installation of my Automatic Passenger Side Window modification. It is relatively simple (after I figured it out finally). This modification is on the basis of a Right Hand Drive 97-01 BB6 VTi-R Prelude. The goal of this modification is to make the passenger side window be able to have [Auto Up] and [Auto Down] while retaining a factory look and feel.

This guide will assume you have common knowledge of removing door cards etc.



Tools:

• Soldering iron
• Side cutters
• Screw driver
• Multi-meter (Optional, but recommended)
• Tape/Heat shrink
• Female spade terminals
• Dremel

Parts Needed:

• Early production "Generation 1" right hand drivers side door multiplex and wiring pigtail.
  • Part Number: 35750-S30-JO-M1
  • This switch is used as it is easier to control remotely, and does not have extra safety contacts in the switch.
    [SPOILER="Identification of 35750-S30-JO-M1"]
  • Right hand drive, Auto switch on the right.
  • Solid black covering on the bottom of the unit.
  • Right hand hole has a different style of contact over-ride for the switches.
    
  • 2x SPST normally open relays.
  • Right hand drive preludes: A left hand drive window motor (America etc).
  • Left hand drive preludes: A right hand drive window motor (Australia, Japan etc).
  • This must be a 4 wire motor.
• To make the drivers side passenger switch automatic as well, you will need a spare drivers side switch and internals.

Very quick step list for disassembly, it's the wiring that counts (follow the service manual here):

Door disassembly and window motor installation

1. Remove the passenger door card.
2. Lower the passenger window, remove the glass.
3. Unplug the passenger window motor, and remove the window regulator from the door.
   • This is a good time to also inspect and lubricate your window regulator.
4. Remove the passenger side window motor, and install the driver side motor into the regulator.
   • Remember, its the opposite driver side than the Prelude you have.
5. Reinstall the window regulator and reinstall the glass.

That's the easy part done, next up, you will need an eye for detail. We are going to be jamming the drivers side switch/computer module into the passenger side fascia. I'll add some extra detail for this part.

Window switch computer disassembly

1. Grab the drivers side switch and remove the black backplate.
   • Be careful as there are electronics behind it.
2. Remove the screws in each corner of the PCB
3. Using a soldering iron, de-solder these two pins while gently pulling the board up.
   • I'm using a "Generation 2" driver side computer as a example, you can see the different window override contact
     
4. Once you have the board free, lift up the board, and you should be able to see two more screws holding the switch contacts.
   • Be careful not to damage the ribbon cable.
5. Put the board aside, that's for later.
6. Remove the window lock switch from inside as well, it wont be needed.
7. Remove the sliding contact from the bottom of the blank switch.
8. Remove the light prism.
9. Flip the casing over, and remove the left side switch (the one that doesn't say "AUTO"), you can easily do this by tilting the switch up (like you are raising a window), but apply more force, it should pop off.

Switch casing modification

This section I can not really help with, but here are some tips.

Grab your passenger side fascia and offer up the driver side switch casing to it. You should be able to see what is conflicting and what needs to be removed.

I basically cut off the entire passenger side switch, but do it as you go. "You can always remove, but you can never add"


You will also need to remove the two tiny pins on the side of the automatic switch cover. After getting the casing and switch fitment to your liking, we need to be able to join the two.

Place the switch + switch casing into the fascia, and identify where the two mounting pillars (for mounting the original passenger switch) meet the switch casing. You will need to drill holes in these locations. Make sure the screw heads do not interfere with the circuit board!

Washers can be used to add or remove switch height.



Circuit board bypass

This is a required step if you wish to still be able to control the passenger side window, as well as passenger side window lock. You will find 7 pins on the back side of the circuit board, opposite of the switch contacts. We only care about 3.

• Pin 1: Down signal
• Pin 2: Up signal
• Pin 3: Automatic activation (works for both up and down)

Solder a wire to each of these contacts, having enough length for later. Re-assemble the circuit board back into the casing, you should have something like this:



Wiring it all up

Now that we have created this abomination, it's time to make it do what we want it to do, and the best part is, it's simple.



*Depending on your wiring pigtail for the switch unit, pin outs may be different wire colours. Stick to wire colours over the pin number

So the things we need to connect:

• Window Motor
  • RED/BLUE - Reversing current
  • RED/YELLOW - Reversing current
  • RED/WHITE - Pulse signal for AUTO function
  • BLACK - Ground
• Driver Switch
  • GREEN/WHITE - Positive
  • RED/BLUE - Reversing current window control
  • RED/YELLOW - Reversing current window control
  • BLACK - Ground
  • RED/WHITE - Pulse signal input
    • Bypass
      UP
      DOWN
      AUTO
• Existing wiring in the passenger door for driver control
  • BLUE/YELLOW - Reversing current window control
  • BLUE/BLACK - Reversing current window control
  • BLUE/RED - Reversing current
  • BLUE/WHITE - Reversing current
  • BLUE - Positive

That concludes what I have currently done myself. The remaining Red/Black and Red wires will hook up to the interior illumination circuit, and the AUTO wire will hook into the driver switch (you will have to make a contact for the switch, that will be added below when I get around to it.)