Range Rover electrical Gremlins

I have just replace the heater blower motor and matrix in my 92 200tdi classic. I taped all the connections and marked them before dismantling, Took it for a test drive today and the blower only comes on when switched to level three. But even worse it also comes on when I accelerate???????? Any ideas would be appreciated.

Silly question - did you check fan speeds before putting dash back together?
If it worked then, then it might just be a dodgy connection.
There is also an electrical gubbins that can fail and restrict fan speed on lower settings. Someone with a lot more knowledge than me will be along sometime.

There is a resistor 'pack' under the windscreen scuttle that can fail and only allow full speed on the fan.....worth checking out....why it also comes on when accelerating is odd...recheck for loose connections.

Yes I did check fan speed and it was only working on the highest speed. I figured I would sort that out in a week or so when weather was better. Didnt think it would cause a prob elsewhere, for the time being. (Should of known better with electrics). Ive been reading about the resistor, and symptoms seem to lead towards that, (which I think you may mean by electrical gubbins)? The replacement blower came with different coloured wiring to the original that was way to short to reach the main feed connector so I had to reuse the original blower wiring. Luckily I have disposed of the redundant air con, so wont be too bigger job getting back in there to replace the resistor.

Damage said:

Yes I did check fan speed and it was only working on the highest speed. I figured I would sort that out in a week or so when weather was better. Didnt think it would cause a prob elsewhere, for the time being. (Should of known better with electrics). Ive been reading about the resistor, and symptoms seem to lead towards that, (which I think you may mean by electrical gubbins)? The replacement blower came with different coloured wiring to the original that was way to short to reach the main feed connector so I had to reuse the original blower wiring. Luckily I have disposed of the redundant air con, so wont be too bigger job getting back in there to replace the resistor.

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Removing the air con on a classic doesn't affect the PITA getting to the resistor pack. It was a while ago when I did mine but pretty sure there is no really viable option than remove the bonnet, then the scuttle and then you can swap the resistor pack which takes about 2 mins!

classic kev said:

Removing the air con on a classic doesn't affect the PITA getting to the resistor pack. It was a while ago when I did mine but pretty sure there is no really viable option than remove the bonnet, then the scuttle and then you can swap the resistor pack which takes about 2 mins!

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Mine was just hanging out of the blower unit? After your comment Ive had a google on RRC HB Resisters and they seem to vary abit. Someone had been inside the dash on mine before as many of the screws were missing and the Blower unit was missing its most difficult bolt! This is similar to the resistor I found when dismanteling!https://www.google.co.uk/search?q=R...AUICygC&biw=1664&bih=938#imgrc=GJ9DR78-izhu3M:

I believe the earlier ones are under the scuttle & later are with the blower unit. Been a few threads on various LR sites where people have removed the scuttle & no resistor present. I don't know when the position was changed.
ETA https://www.landyzone.co.uk/land-rover/classic-heater-blower-issues.83152/

Ok so replaced the restrictor in the heater box but still had the same symptoms. So took off the decker grill for a peep inside. Found another restrictor, although this one has an external copper wire wrapped around it that was basically non existent in places. 4 spade clips with one totally disintegrated. So have ordered the Atlantic British design, upgrade replacement. So it appears that by at least 1992 RRC were fitted with both.

New resistor pack finally came. All fitted, decker panel back on, dashboard back on, Tested heater controls and now works on all three settings, revved engine and blower didnt come on, so went for a drive. Once again when I start climbing a gradient on comes the blower motor, and my rear drivers side indicator blows????????? So figured that As the wiring from the new blower is yeallow and brown and that the wiring to it is red and black, I may of got them the wrong way round, so just took dash apart again swapped the wires round but yet again blower comes on when I reach a gradient? At a complete loss now.

Does it come on to give you impression your going really fast?
Or are you going really fast and it's not the fan coming on??

Mark Piercy said:

Does it come on to give you impression your going really fast?
Or are you going really fast and it's not the fan coming on??

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I am now feeling really stupid and now and after this post I will go and sit in a corner for a while in shame!
My blower was trash so replaced it, but my confidence in electrics is zero. So when the new Item arrived with different plug and wire colour I wired it up to whatever logic I had at the time. The blower only worked on number three setting. And appeared to come on at a faster speed when I put the engine under load. After alot of reading I found a second resistor under the decker panel, as discussed above. This resistor was visably shagged so replaced it. Only to find that the noise was still there when driving with engine under load.

I assumed that this was some mistake I had made with the wiring and that when the revs got high it sent too much voltage to the blower making it spin faster than normal. With my indicator blowing a new bulb everytime I tested the RR and my inability to understand electrics I felt this verified my theory.

I tried messing around and re testing wires etc. Before deciding that as I desperatly need the car I would just unwire the blower and deal with it another day.

But on the next drive the noise appeared again as soon as I hit the slope on the road.

Totally stumped I explained all to the wife, and asked her to sit in the passenger seat and try to work out what the hell the noise was as the blower is not wired and I couldnt do it while driving.

Turns out it was a hole in the passenger footwell where the air con hoses used to be. It only makes a noise when climbing up hill above 20 mph. But sounds exactly like a blower on high speed. My lack of faith in my ability to do wiring had led me to assume I messed up somewhere. If I hadnt just replaced the blower I probably would have found the real problem straight away.

So heater now works on all speeds. I feel like a complete ****. And now have to find out why my indicator bulb keeps blowing.

Thanks for the help guys!

You can't win em all buddy, at least you have an answer
Where's the little face laughing and piddling??