After pulling my 200tdi RRC out of the barn from its rebuild, the temperature guage has failed to work. I changed the sensor with no joy, so while twiddling my thumbs waiting for parts to arrive I decided to test the wires that go to the sensor. And found that they are completely dead. I dont pretend to know anything at all about electrics, but I have been having this problem alot. The other most recent example was that I replaced the blower motor, which worked fine for a week then nothing. After days of fiddling and testing it turned out that for some reason the power feed to the switch had become dead????. Does anyone know where the feed to the temp sensor on the top of the thermostat housing comes from please???
Temp sensor feed wire dead!
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I assume the engine is the same as a Disco?
If it is then the temp sender for the dash gauge is in the side of the thermostat body and the one/s in the top of the stat housing where the top rad pipe comes off are for the A/C.
You got a picture?
LRcat shows it in the side of the housing:
Item 9 AMR1712 http://new.lrcat.com/#!/1229/83488/83961/6646/84398
Item 9 AMR1712 http://new.lrcat.com/#!/1229/83488/83961/6646/84398
I always assumed that the twin spade sensor on top dealt with the temp guage, as I have been searching for a single female spade clip wire that would go to the sensor on the side for over 6 months now? I removed the engine for a comnplete rebuild but taped all wiring for refitting. I assume that the single clip sensor would just have a single wire running from it direct to the gauge on the clock panel?????
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Aircon ones them.
First pic, look just behind the blue silicone pipe and you will see the actual temp sensor for the gauge.
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No, the lower sender shows mean engine temp from cold as the top sender is above/after thermostat which will only open once the engine up to temperature if that makes sense as that sender is for the operation of the AC fans in front of the radiator.
Ive disabled and removed all air con so guess I dont need the top sensor wired up anymore! But cannot for the life of me find any wire that could go to the lower sensor? Would it be just one wire from dashbord guage to that sensor? Maybe I could just make one if it is?
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At a guess that is supposed to plug into the connector for the AC pump judging by the rubber "O" ring on the plug which would mean it was a male that fitted a female.
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See below.
All makes sense.
I will just pop and see what colour wire the temp sender wire is.
BRB
Ahhhhhh that makes sense! the pump was removed before I bought it, and rather than replace it Ive just removed the rest of the AC, (only more to go wrong and would have stopped me fitting full size intercooler).
Yes seems like the best option, although so far no wires have yet proved to match the right colours, lol. But I do love challenges once I have remedied the problems, lol. Thanks for your advice sometimes it takes an outside look to tell me what should be common sense!
Is this a factory 200TDi or a conversion from a V8 or VM?
You need a wiring diagram to show you what wire should go from the sender & where it goes to.
ETA Don't know if this is of any help, later wiring diagrams are towards the bottom:
http://www.landroverweb.com/Pdf-files/Manuals/Range-Rover-Maunual-Electrics.pdf
You need a wiring diagram to show you what wire should go from the sender & where it goes to.
ETA Don't know if this is of any help, later wiring diagrams are towards the bottom:
http://www.landroverweb.com/Pdf-files/Manuals/Range-Rover-Maunual-Electrics.pdf
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Been having a play on the diagrams & it looks like the live feed goes to the gauge, then to the sender unit & is earthed through the sender unit itself so that might be a starting point.
Appears on those diagrams the wire colour from gauge to sender is Green with a Blue trace - the LR manual for mine (big thick book) which covers MY1986 through MY1989 V8 petrols and VM diesel shows the same colour coding so presumably could be the same on the later diesels.
IIRC testing for a faulty sender is by touching its single wire to a good earth & with the ignition on the gauge should go to the top of its scale.
Appears on those diagrams the wire colour from gauge to sender is Green with a Blue trace - the LR manual for mine (big thick book) which covers MY1986 through MY1989 V8 petrols and VM diesel shows the same colour coding so presumably could be the same on the later diesels.
IIRC testing for a faulty sender is by touching its single wire to a good earth & with the ignition on the gauge should go to the top of its scale.
Thankyou very helpfull, yes it is a factory fitted 200tdi! Will update at end of the day.
Ok so big thankyou for all your replies! especially Ratae, I didnt get chance to deal with the prob the other day, due to finding welding to do! but went out this morning. Removed the clocks, found the green wire with blue trace, and as usual it disappeared into the wrapped loom. So went into the engine bay and found it coming out of a plug, and disappearing into another wrapped load of wiring that hugged the bulkhead behind the engine, that contained the alternator, and solenoid wires, but the green and blue wire was nowhere to be seen? After stripping back the wrapping quite a way, I found the green and blue wire. It must have broken and got pulled back up into the wrapping. After a quick test my son verified that the temp gauge worked, so I rummaged through my barn and found an old disco loom that had a g/b wire that I could use. All in all a job that I had kept starting, and giving up on, for well over a year now took me approximately an hour, once I knew what colour wire to look for. So I have learnt two things, 1). learn to understand wiring diagrams and get over my mental block on auto electrics, and 2). I need to buy Ratae a pint if ever we meet.!
