MK4 Golf Climatronic install into MK2 Golf

Discussion in 'Electrical' started by rubjonny, Aug 7, 2013.

  1. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    Hello all, I feel electrical section is the closest match for this one :lol:

    as some of you may know I've been busy installing climatronic into my MK2 Golf, which to my surprise wis easier than I was expecting!

    the main difficulty apart from the wiring is mounting the control unit, as I made life difficult for myself and decided to keep the MK2 dash and fit the unit where the MK2 sliders used to be. plus I wanted the stereo to remain in the factory position as I find they look a bit rubbish in the console due to you having to cut out a slot from the edge. Fitting it to the console would be a lot easier, in fact chucking in the whole MK4 dash might have been easier tbh :o

    anyway it takes a fair amount of chopping as you can imagine. First off cut up the dash surround till you can get it to sit nice:
    gti57.jpg

    then you also have to cut out a fair chunk of the dash itself as well as the metal behind it. take care to leave 2 'tabs' you can bend up and drill holes in for the 2 lower screw fixings. The main reason for dash chopping is the climate panel is a lot taller than the mk2 sliders so it needs to be 'sunk' into the dash a bit:
    gti60.jpg

    I made another bracket up for the upper left fixing from a bit chopped out of one of the clock holder brackets, I used a self tapping screw tab nicked out of an aftermarket cl kit pushed into the dash material for the screw fixing if that makes sense (I used another for the climatronic fixing on the outside so you can see what I mean)
    gti59.jpg gti58.jpg

    I haven't made anything for the upper right hole mainly as it was really hot that day and I ran out of assed-ness, but it seems nicely solid with just the 3 fixings. I'm hoping once the outer trim is cut to fit this will also help brace the unit to the dash surround trim. Anyway here is the finished article, I still need to make a trim to cover the screws I'm hoping the mk4 climatronic trim suitably trimmed will do the job but if not it wont be hard to make something up. Note how the stereo still needs to be moved upwards as high as possible even when you sink the climate unit into the dash, so even more dash trimmage is required at the top:
    gti56.jpg

    And that's the hard part out of the way! See the following pics for comparisons between the mk2 and mk4 airbox assemblies:
    climatronic1.jpg climatronic2.jpg climatronic3.jpg

    as you can see they're pretty much identical! the middle box top stud is slightly lower than the mk2 so you either need to add a stud at the top of the mk4 airbox in the mk2 location or do what i did and drill a new hole in the bulkhead. the box sits off the bulkhead though so you need to fit a spacer in the gap ideally (maybe I'll get round to that one day :lol:)

    fan blower assembly, again very similar:
    climatronic5.jpg climatronic6.jpg

    you just need to add a bracket at the left side to the mk2 stud, or you might be able to use the MK4 rubber with a fixing drilled into the mk2 dash bar, it does look close but I cant see 100% as I am not going to drill the hole in the bulkhead for the studs and aircon rad outlet yet as for the moment I'm just gettign the mk4 climate installed without the aircon side working for now. For this I am going to mount the mk4 blower resistor and inlet sensor into the mk2 blower housing and do without the recirculation, this also means I dont have to mod my glovebox or shelf to fit with the massive aircon blower unit (I have enough to do right now!!)

    Wiring wise you need to get a complete mk4 harness, then its a case of chop out the climate section and you are left with ignition live, live, lights on and earths to splice to power it. then you'll need a speed signal (MK2 GTI cluster outputs this to the radio so steal that, rev counter signal (need a MK3 type signal, if you have a mk3 golf engine sorted. if not use pin 7 of the TCI unit), diagnostics port ideally for fault diagnosis and thats pretty much it. Main headache is deciding how you will run the engien bay wires. In my MK2 I ran them all into the lighting loom and added an 8 pin connector behind the fusebox to keep it modular like factory mk2. you could use one of the many spare bulkhead grommets.

    for the aircon pipes the MK4 ones look like they'll work well enough, same with the aircon rad and drier. if not then MK3 golf or SEAT ibiza/toledo/cordoba stuff should do the job nicely. for the compressor it depends what engine you have, but for a big block mk2 convert your engine to late mk3 golf alternator setup with the separate tensioner wheel, source a mk3 aircon waterpump pulley and rear pump bracket then I think the mk4 aircon pump will bolt up? if not use a mk3 aircon pump :thumbup:

    Will keep this thread updated as things progress with my build :)
     
    Last edited: Mar 30, 2023
  2. Trev16v

    Trev16v Paid Member Paid Member

    Joined:
    Oct 22, 2003
    Likes Received:
    451
    Location:
    Oxfordshireland
    Good grief! Amazing work. Will enjoy seeing the progress of this.
     
  3. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    cheers trev means a lot coming from you :thumbup:

    Complete list of the climatronic unit, main unit to sensor & motor wiring loom and the radiator fan control unit plugs. The main ones to worry about are the T12a and T14a plugs, this is where the main Climatronic unit loom joins the rest of the dash harness plus there are a couple wires to the MK4 fan control unit. The connectors on the control panel itself are just included for completeness:

    T12 black - on climatronic control unit -A-
    1 - gry/wht - diagnostics K line
    2 - brn/blu - 'A/C requested' (A/C switch 'on'), rad fan control unit T14/8 (mk4) ecu connection T80/10 or T24c/14 (passat)
    3 - blu/red - ecu pin 10 or 40 (mk4) n/a (passat)
    4 - brn - n/a
    5 - gry/pur - dash lighting
    6 - gry - n/a
    7 - brn/grn - fresh air duct temp sensor
    8 - brn/yel - outside air temp sensor, behind bumper
    9 - brn/wht - climatronic sensor common ground
    10 - blu/blk - n/a (mk4) wiper relay pin 58c (passat)
    11 - blu/pur - n/a (mk4) 5v duty cycle signal from cluster (0% = overheat) (passat)
    12 - brn/wht - climatronic sensor common ground

    T20 red - on climatronic control unit -B-
    1 - red/blu - ambient temp signal from dash clocks
    2 - org/grn - CAN-BUS high (passat)
    3 - org/brn - CAN-BUS low (passat)
    5 - gry/grn - footwell vent temp sensor
    6 - brn/red - n/a (mk4) centre vent temp sensor (passat)
    8 - yel - heater flap control motor
    9 - yel/wht - centre flap control motor
    10 - yel/red - footwell/screen control motor
    13 - yel/blu - n/a (mk4) time parked (passat)
    17 - wht/pur - air flow control motor
    18 - wht/grn - sunlight sensor in top of dash

    16b brown - on climatronic control unit -C-
    2 - blk/wht - rad fan control unit T14/12 (mk4) a/c pressure switch (passat, early mk4)
    3 - blk/blu - battery live feed (passat)
    4 - blu/wht - vehicle speed signal
    6 - grn/pur - engine speed signal
    7 - gry/blu - n/a (mk4) wiper relay pin 58e (passat)
    8 - red/yel - common 5v feed for positioning motors
    10 - yel/red - n/a (late mk4, passat) a/c pressure switch pin 3 (early mk4)
    11 - brn/red - blower motor & blower motor control unit earth reference (assume this is so it knows how fast fans are spinning?)
    12 - grn - ecu pin 10 or 41 'A/C ON' (all sensors report OK, compressor engaged) (mk4) ecu connection T80/8 or T24c/11 (passat)
    14 - blk/blu - ignition live feed tapped to blower motor +
    16 - grn/blk - blower motor control unit

    16a black - on climatronic control unit -D-
    2 - wht/yel - heater flap control motor
    3 - gry/yel - footwell/screen control motor
    4 - wht/pur - centre flap control motor
    5 - wht/gry - air flow control motor
    6 - grn/brn - compressor relay trigger (passat, earth trigger)
    7 - brn/blk - permanent live feed
    8 - grn/brn - aircon clutch control relay earth trigger (passat)
    9 - blk/blu - ignition live feed 10a
    10 - gry/wht - heater flap control motor
    11 - wht/red - footwell/screen control motor
    12 - gry/red - centre flap control motor
    13 - gry - air flow control motor
    14 - brn - earth (passat)
    15 - brn - earth
    16 - rad fan speed 1 control relay earth trigger (passat)

    T12a - on climatronic loom to main car harness:
    1 - grey/white - diagnostics K line
    2 - brn/blu - a/c on signal, rad fan control unit T14/8 (mk4) ecu connection T80/10 or T24c/14 (passat)
    3 - brn - n/a
    4 - gry/blu - n/a
    5 - brn/yel - outside air temp sensor, behind bumper
    6 - blu/blk - n/a
    7 - yel/blu - n/a
    8 - wht/grn - sunlight sensor in top of dash
    9 - blk/wht - rad fan control unit T14/12 (mk4) a/c pressure switch (passat, early mk4)
    10 - blu/wht - vehicle speed signal
    11 - gry - n/a
    12 - red/blu - outside temp signal to dash clocks pin T32a/26 (feeds the temperature display on the clocks)

    T17a - on climatronic loom to main car harness:
    1 - blk/blu - ignition live to blower fan and control unit (25a fuse)
    3 - blu/red - ecu pin 10 or 40 (mk4) n/a (passat)
    4 - grn/brn - engine speed signal
    5 - blk/blu - ignition live
    6 - brn - earth
    7 - red/gry - permanent live feed
    8 - brn/wht - climatronic sensor common ground (for outside air temp sensor & sunlight sensor)
    9 - pur/yel - n/a
    10 - gry/blu - dash lighting
    11 - yel/red - n/a (late mk4, passat) a/c pressure switch pin 3 (early mk4)
    12 - grn - ecu pin 10 or 41 (mk4) ecu connection T80/8 or T24c/11 compressor switch off? (passat)

    T4a - on fan control module
    1 - red/blk - 12v input for 2nd fan speed
    2 - red/wht - 1st speed fan power output (a/c on)
    3 - red - 12v input for 1st fan speed
    4 - red/blk - 2nd speed fan power output (overheat/pressure)

    T14 - on fan control module
    1 - red/blk - feed for electric water pump (only for 5/6 cylinder engines)
    2 - wht - pressure switch pin 2
    4 - red/gry - 12v power for control module
    5 - grn/blu - to ambient temp sensor some models, or looped to T14/14 on MK4
    6 - brn/blk - earth for control module
    7 - red/yel - fan thermoswitch pin 3 (overheat, 2nd speed trigger)
    8 - brn/blu - climatronic control unit pin T12/2 (goes through T12a/2, a/c on signal)
    9 - blk/blu - ignition live feed
    10 - grn/blk - a/c compressor clutch pin 1
    11 - brn/wht - only for TDI ECU
    12 - blk/wht - climatronic control unit pin T16b/2 (goes through T12a/9)
    13 - pur/yel - 5v duty cycle signal from cluster (I believe earthing this will switch off AC and trigger fan, could be wired to simple thermoswitch)
    14 - grn/blu - to ambient temp sensor some models, or looped to T14/5 on MK4



    Also this might interest those with wiring fetishes, here's my finished dash loom containing the MK4 Climatronic, convenience module, stereo, diagnostics, ciggy lighter and vdo wires (will try to put a thread up on the CCM install soon!) as you can see its quite a bit more complicated than mk2 and this one doesn't even have dash switches, clock loom or stalks in as I wanted to keep them separate/modular as per factory CE2! To the left is the fusebox side, only 1 of those plugs actually goes to the fusebox the rest are for other joins for door locks, climate to engine, cl wires to rear loom, etc etc :lol:
    gti61.jpg
     
    Last edited: Oct 26, 2023
  4. Blue MK2 Forum Member

    Joined:
    Dec 9, 2003
    Likes Received:
    6
    Location:
    United Kingdom
    Awesome RJ!
     
  5. Finite

    Finite Paid Member Paid Member

    Joined:
    Nov 20, 2004
    Likes Received:
    255
    Location:
    Northamptonshire
    Very interesting and great pics, this could be something I could scavenge off my mates cat C Mk4. Will you be weighing the main parts to see what the extra payload is?
     
  6. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    If I remember! I've already fitted the central vent housing to the car though and it was a real pain on me own so I wont be taking it off again unless I have to :lol:
     
  7. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    alrighty peeps! some progress.

    As it turns out the lower stud isn't the same height as the MK2 one, its around 10mm too low plus the box ends up a bit too close to the bulkhead and needs spacing out a touch. so if any of you decide to go this route be sure to take measurements of the mk2 airbox position before you carry on with the swap!!

    I drilled 2 more holes and slotted them to provide more adjustment, plus used nuts on the mk4 studs to space it out a bit. If I was to do it again I would make up some metal brackets to go between the MK4 airbox stud holes and the mk2 bulkhead holes, wouldn't be too difficult to do really but I just wanted it in as car has been off the road for too long as it is!

    anyway, everyone loves pictures! 1st thing I did since the last update was convert the MK2 blower housing to take MK4 parts. The reason for this is I need to really get cracking with mk2 on the road and making the holes in the bulkhead for the mk4 blower unit plus chopping up the glovebox and under-tray for clearance would take too much time, I'll come back to this job later.

    First up I chopped a square hole in the mk2 airbox to take the MK4 fan resistor, then you just use a couple self-tapping screws to secure. Then drilled a large round hole and chop a couple of ears in it for the inlet air temp sensor. The recirc flap I left off as it was too much work to make it fit. Note that I only just got away with the position of the resistor, its tight to the mk2 dash bar thingy. The plug JUST clears, and you cant plug it in when the unit is in situ unless you disconnect it from the airbox and tilt it down a bit. If I had thought about it a bit more I would have put it on the front instead!
    gti63.jpg

    Then I bolted it all in the car, thinking everything was tickety boo. But then once I tried to fit the blower vent assembly I found it was too low. lesson learnt:
    gti64.jpg

    Then more effort brings you to this stage:
    gti65.jpg gti66.jpg gti67.jpg

    and finally:
    gti68.jpg

    Just need to get a MK4 climate trim to cover the edges, or I'll have to make something custom. This can wait! Once the radio went in the bit of trim under the buttons is very close, there is just enough room but I may need to trim it out a little for clearance later we'll see how it goes.

    Some other notes while I think of it, on the driver side the MK2 side trim piece goes on pretty well, there is an inlet sensor in the way but it bends over it without too much trouble. the passenger side however will need some thought as there is a vent motor linkage that pokes out, if you have ever looked at a MK2 the only piece down here is a bit of foam which also covers the blower assembly. it will bend over the linkage no problem but it doesn't offer any protection so I will need to get some kind of plastic trim to go over the top. Will be looking at MK4 golfs at some point to see what they have there!
     
    Last edited: Mar 30, 2023
  8. 35i-GTD New Member

    Joined:
    Oct 31, 2013
    Likes Received:
    0
    Nice work!
    I've thought about doing the same in an old B3 since i'm converting to Mk4 dashboard :)
    I guess you didn't apply the AC-peace since its an Mk2?
     
  9. gixerboyuk New Member

    Joined:
    Dec 27, 2009
    Likes Received:
    1
    Location:
    Derby
    So is a climatronic thing all self contained or is there more gubbins under the bonnet like an air con set up? (Forgive my ignorance never had a car with climatronic)
     
  10. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    35i-GTD: I have all the parts I need to fit full aircon, except I might need a 4 cylinder mk4 compressor pulley as mine is from an r32, or I may have to get a MK3 Golf compressor if the mk4 one doesnt fit. I stopped short of fitting full A/C at this stage mainly because I couldn't be bothered, as I'll have to chop up my glovebox and dash undertray to fit it (I did have genuine mk2 a./c bits but sold them thinking I'll never get round to fitting a/c :lol:) Hopefully I can mod it in such a way I have some usable storage after but we'll see! For the bulkhead I just need to chop 2 holes 1 for the compressor and another for the drain bung. wiring is all complete I made sure I sorted that as I dont fancy stripping out the bay looms again any time soon! was a real mission to make the bay side of the a/c loom unplug nicely from the internal section. Mainly I did this to retain the nice CE2 modular wiring system, If I had converted it to full MK4 fusebox style it would have been a hell of a lot easier

    It works perfectly as it is, except for no a/c obviously and the recirculation doesnt work either as above it cant be modded into a mk2 housing without serious effort. I love it [:D]

    gixerboyuk: well, if you dont care about having aircon you can do as I have done, leave out all the aircon bits and just fit the face panel and central blower unit. There is also a radiator fan control unit under the bonnet I have wired this too since I will eventually want aircon but since its winter I havent bothered with it just yet!

    if you want aircon there is the usual compressor, pipe work, pressure switch etc. the really early mk4 and passats didnt have a fan control unit instead they used a different pressure switch which is wired direct to the climatronic unit. I assume the coding on the unit is different but you can change this in vagcom I believe?
     
  11. 35i-GTD New Member

    Joined:
    Oct 31, 2013
    Likes Received:
    0
    So, lets say that if I take the whole AC/clima-system from my G3 spare-car and fit it in my 35i. Then buy an Mk4 fan-box and Climatronic-unit.. together with a Mk4-fusebox that i'm getting from the dashboard-swap, will get this conversion easier?

    I think my AC-compressor will fit mine great, since they got basicly the same engine (AAZ and AHU)
     
  12. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    yeah the basic a/c pipes, rad and compressor are the same for both (different shapes and such, but they work the same I mean) you dont even need climate specific parts in the engine bay its same stuff as basic a/c the difference is all in the central fan box and wiring!

    you will probably have to change the a/c pressure switch unless you manage to locate an early mk4/passat unit which uses the old style 4 pin switch rather than the newer style 3 pin. take the fan control box from the donor mk4 as well if its a later one, you can then tap this into your fast fan speed wiring if you like. I didnt on mine as the stock mk2 fan has no need for fan relays so didnt see the point of adding it, but the main reason was that I dont have a source for the huge pins that go into the relay box and the wires on the MK4 are too short to reach. splicing wires together to extend isnt my style :lol:

    I still have the trigger wires from the fan switch connected to it though, as these wires are required to tell the fan unit if the engine is getting too hot I believe? What I did do with my fan wiring while it was all apart was run the live feed to the MK4 battery box direct rather than to the fusebox, takes a bit of load off the MK2 fusebox
     
  13. murph81 Forum Member

    Joined:
    Feb 23, 2010
    Likes Received:
    66
    Location:
    Republic of Ireland.
    Toyotec has just removed Genuine AC from a Mk2, might be worth a call!
     
  14. sparrow Paid Member Paid Member

    Joined:
    Jan 2, 2006
    Likes Received:
    741
    Location:
    Leamington Spa
    Sorry to RJ for the blatant profiteering of his work, but I'm breaking my Mk4 if anyone needs the parts. ;)
    I'll buy him a beer if anyone does buy the parts. :thumbup:
     
  15. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

    Joined:
    Jul 26, 2006
    Likes Received:
    3,320
    Location:
    Creating Pfredstarke
    My A/C was aftermarket and was removed and junked due to it's poor state
     
  16. murph81 Forum Member

    Joined:
    Feb 23, 2010
    Likes Received:
    66
    Location:
    Republic of Ireland.
    Sorry I thought it was genuine, I knew the condenser was shot but thought there might be some salvageable parts.
     
  17. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

    Joined:
    Jul 26, 2006
    Likes Received:
    3,320
    Location:
    Creating Pfredstarke
    The whole lot was aftermarket, including the fitment of the evaporator in relation the existing non A/C blower interior trim (glove box).
     
  18. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    cheers guys but im just going to cut the ass out of my glovebox and undertray :lol:

    I have all the mk4 bay parts so should be fine there, worst case might need a mk3 compressor to fit my abf lump but that shouldnt be too hard to find. fingers crossed a mk4 one fits as much easier to get them
     
  19. Steve B Forum Junkie

    Joined:
    Oct 25, 2003
    Likes Received:
    36
    Location:
    Manchester
    epic conversion, and here I am putting off yet another heater matrix change! (3rd car)

    the only thing I really miss on my mk2 is the ability to close the air off from outside, but thats mainly because when i drive it at the moment with no heat in the matrix, im just getting cold air blown at me on a cold day.

    let us know how the trim looks when its all on!
     
  20. Sean_Jaymo Forum Member

    Joined:
    Sep 17, 2012
    Likes Received:
    5
    Location:
    Lincolnshire
    Epic mod, I fitted this earlier in the year to my Corrado. It's not actually that difficult on the wiring and even easier if you ignore the actual AC part. Only ever seen it fitted to 2 or 3 other mk2's as well so nice one!
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice