Defender Variable Heater Fan Control Mod

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KISSMYAURA

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Variable heater control Mod from Dutch company.
they have sent me the english instructions, but the translation is appalling, wonder who they used Noddy?
(WTF is a beldon cable and what valve is connected to the fan heater switch :D
1) Beldon cable means wire-cable?
2) Valve means vents?
That aside it seems straight forward enough though, I think they are saying open heater fan switch to position 1, ie no fan just vents open and lock off cable in this position.
The rest of the instructions are poor and most of the pictures are not helpful. I am assuming they have employed the 'Haynes Manual' photographer, no one else has the ability to take pictures of things to make them completely unrecognisable (even with a LHD) and from angles that defy the laws of physics, nevertheless the final picture makes does make some sense!
Seems like a nice little mod its around 100 euros inc shipping.

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Handleiding Kachelaansturing EN - 90.04.VPWM2.jpg




Yes you could make this yourself using a Variable speed controller (VSC ) or Pulse Width Control module (PWM ), if you are confident with elecytrickery and can wield a soldering iron like a jedi. The motor control circuit is fairly simple. An ignition switched 12V feed is fed to the blower motor from the fuse box. This is then earthed by the speed switch on one of two wires - one of which has a resistor to limit the current and produce a slower speed.
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From what I can tell it gives modern fam control. Not just little bit and full blast, or in some cases just full blast! Its be nice to have just a trickle of hot air sometimes rather than having to constantly turn it on and off.

Would be good if the did one for the temp control, be nice to have a varying degree of heat bar just hot

I do plan to overhaul my entire heater unit over the summer, its alright but no fantastic, certainly not as good as my old 90. Though I believe thats down to the replacment heater box its had of unknown quality.
 
I'm with you, isnt the standard control already variabvle? Mine at least is more than just on or off and has a few differant speed settings.
I appreciate Landy’s don’t have the greatest heaters/blowers in the world, but mine has 3 different fan speeds which seem to do just nicely. An infinitely adjustable blower is probably great, and if you’ve got the money to blow then maybe. But I don’t fall into that category at all!
 
I appreciate Landy’s don’t have the greatest heaters/blowers in the world, but mine has 3 different fan speeds which seem to do just nicely. An infinitely adjustable blower is probably great, and if you’ve got the money to blow then maybe. But I don’t fall into that category at all!
Also with all of the other gaps and drafts in mine it spends its whole time on full anyway! If I turn it down I get cold air blowing at me from the door seals and foot wells rather than warm/less cold air from the heater
 
Same, full from about October-March, off all summer.

All defenders have two fan speed settings ( turn on your ignition, don't start engine move to click one, no air and no fan spinning)
(0)*First click opens the internal flap from closed
(1) Second click is low speed Position (1) in text below
(2) Third click is high. Position (2) in text below.

If you are moving it will seem like three speeds.

The owners manual says the lever has four positions.
1 - off (top)
2 - allows air flow into cabin from movement of vehicle (click 1)
3 - slow (click 2)
4 - fast (click 3)

More detail for anyone thats interested!

*( ) number relates to text below relating to position number only.
Feed from the positive battery terminal is connected to the engine compartment fuse box by a brown wire. Current passes through fusible link 2. Fusible link 2 is connected to the ignition switch by a brown wire.

With the ignition switch in position "l", power flows through the ignition switch to fuse 5 of the passenger compartment fuse box by a white/orange wire. Fuse 5 of the passenger compartment fuse box is connected to the blower fan motor by a purple/green wire. When the blower control is in the off position, the blower motor has no route to earth and does not run.

Moving the blower control to position "l", connects the blower motor to the blower switch on a green/yellow wire. Power flows through the blower motor and resistor to the blower switch and to earth on a black wire. The blower fan operates at low speed. Moving the blower control to position 2, connects the blower motor directly to the blower switch on a green/slate wire, and to earth on a black wire. The blower fan now operates at high speed.

Note wire colours may be different this is for def 300tdi 96 > but all switches work the same way.
 
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All defenders have two fan speed settings ( turn on your ignition, don't start engine move to click one, no air and no fan spinning)
(0)*First click opens the internal flap from closed
(1) Second click is low speed Position (1) in text below
(2) Third click is high. Position (2) in text below.

If you are moving it will seem like three speeds.

The owners manual says the lever has four positions.
1 - off (top)
2 - allows air flow into cabin from movement of vehicle (click 1)
3 - slow (click 2)
4 - fast (click 3)

More detail for anyone thats interested!

*( ) number relates to text below relating to position number only.
Feed from the positive battery terminal is connected to the engine compartment fuse box by a brown wire. Current passes through fusible link 2. Fusible link 2 is connected to the ignition switch by a brown wire.

With the ignition switch in position "l", power flows through the ignition switch to fuse 5 of the passenger compartment fuse box by a white/orange wire. Fuse 5 of the passenger compartment fuse box is connected to the blower fan motor by a purple/green wire. When the blower control is in the off position, the blower motor has no route to earth and does not run.

Moving the blower control to position "l", connects the blower motor to the blower switch on a green/yellow wire. Power flows through the blower motor and resistor to the blower switch and to earth on a black wire. The blower fan operates at low speed. Moving the blower control to position 2, connects the blower motor directly to the blower switch on a green/slate wire, and to earth on a black wire. The blower fan now operates at high speed.

Note wire colours may be different this is for def 300tdi 96 > but all switches work the same way.
Alright smarty pants, you’re right. :oops:
 
I hate you Neilly! I'd love a rag top!!

Wasnt there a heater fan upgrade available a while ago? Was some kind of leccy chip that increased the blower speed by about 25% or so, would be useful combined with this.
 
I hate you Neilly! I'd love a rag top!!

Wasnt there a heater fan upgrade available a while ago? Was some kind of leccy chip that increased the blower speed by about 25% or so, would be useful combined with this.
just a 12V dc to dc voltage stepper, up to say 14 volts, ( pennies from ebay) but i would not expect your fan to last very long! It just might spin out of the box and undertake you on the inside!
 

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Would be good if the did one for the temp control, be nice to have a varying degree of heat bar just hot.

Heat is mixsble, well on mine it is certainly
All the way from hot to cold.

It’s mechanical though so not sure the company could make an electrical gizmo.

Are your flaps adjusted okay?
 
yea, heat control is just a simple valve, just reduces flow, so air when on 'low' passing over cools it quicker etc
All depends on speed and outside air temp etc
I like the idea of greater control over fan speed, but would not want to increase the high speed any more.

Another option is a 12v ceramic heater element, but not the pants things you can get on ebay see pics below not cheap through!
Or an Infra red heaters (fitted in diggers etc) around £140 but sucks your battery!
 

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