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Defender heater resistor???

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Still have my resistor unit I bought from simonb on my 110 but it's no longer in use, it still works & I have the instructions that came with it,happy to sell it. 

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Here is a new link to a parts page and the part numbers.  But....I don't believe that LR sells any of the resistors and harnesses anymore.  I "assume" you would be UTP1904.  I'm 90% sure it is discontinued.


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Hello, everybody.

New poster here.  I would also like some help with the heater blower resistor from an oldish ( 1987 ) heater box blower.

I am not necessarily looking for a new resistor, just advice at this point. ( it could be that my existing resistor is fine).

I will happily provide my resistor  to anyone who needs one if I can get my heater working without one.

My heater fuse started blowing in Feb 2019 ( I replaced it a couple of times ), but since then I have just removed it and not run the heater ( or the truck for that matter). 

I have stripped the heater box out ( It's a left hooker - I am in France). The matrix was full of gunk, and corroded, and the fan did not spin that freely, so I suspect the issue might well be the fan motor, and as the fuse blew when I went to use it, maybe the resistor is still good. 

The reason I think ( I know next to nothing btw..) that I might not need the existing resistor is that I am not worried about my heater running at different speeds, I am happy for it to run full tilt the whole time. Furthermore, my ex-mod 110 had had the switch screwed into the Max position (on the dash) since I bought it about 18 years ago, and it has never bothered me since this is all I have known. The noise is not an issue, as it is still hard to hear the blower over the symphony of other sounds:)

If there is a simple way of by-passing this, then I am happy to do this, and offer up my resistor, as I appreciate they are

A) Rare,

B) Expensive

and all I really want is for my blower to run full tilt the whole time.

Attached is a photo is the resistor I have.

Really appreciate your input and suggestions.

Many thanks




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With your description of the motor and housing being full of gunk, your problem is almost certainly the seized motor. I have managed to free a motor in the past, but it depends how badly seized it is. Replacement may well be your best option.

When the heater is on full speed power doesn't run through the resistor. When the fan is set to slow speed, that is when the resistor comes into play. If after sorting the motor problem you find the resistor is bad, you can replace it cheaply with one like I describe in my post further up 


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Hi mickeyw.

Thank you for the reply. As the motor does not turn freely, you are probably spot on. I have ordered a new LHD blower motor - RTC4201  (who knew they were different?). 

Thanks for confirming that if I run on full blast, then the resistor is not used.  


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I finished the rebuild of the heater box and slight modifications.

A new blower (LHD) and a new heater matrix were used ( I padded it out with camping mat as per other threads) and I got a 6ohm resistor in an ally heatsink like the one pictured earlier in the thread. I cut a bigger hole in the bulk head with a 125mm grinder, but I made my own foam insert as I just could not get the new one to fit. I also removed all the slidey ( clunky) switch gear and just put a simple 2 position rocker switch in for fast / slow.  So now its on hot when it is on, and I fixed the hi-lo flappy bit so its about 80% / 20%  for screen / feet.

On fast, it blasts the screen with hairdryer style hot air, but on low it is just slightly stronger than 6 cats farting. I checked the resistance of the old resistor and it was a 2ohm, which explains why my "low" speed is just that.

Still I am very happy with the outcome, so thank you for all the advice higher up on the thread.

Next mini-projects are:

  • remove and clean / replace the sedimentor thingy as it looks untouched for 33 years
  • Get the oil temp gauge working again ( originally it had an oil radiator), but this was replaced when it became a 200TDI.( I am thinking of getting one of those sump plug adaptors, and a new sensor).
  • Get the little convoy light on the diff working
  • rewire the diff lock light so it works again (it used to work, but I disconnected/broke it when I changed the punctured clutch fork & forgot about it and can't remember where it goes :) )
  • remove the hand throttle as it is not connected to anything
  • do something with the volt meter under the red and black radio plugs, as it has never worked
  • replace rear x-member

Given my general incompetence / ignorance, please humour my dumb-ass questions on other threads relating to some, all or any of the above.

Once again, thanks to all.


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