|
||
|
Title: cooling fan( Electrical help )reqd Post by marky on Apr 15th, 2005, 1:18pm Hello Some of you will have read the earlier post on cooling fan running and here is where i am up to . Ultima 2.5TD 1995 Drivers side fan only runs, Checked out the relay (large green one ) behind headlight, the relay works fine , tried it on another scorpio also tried my friends relay on mine and as before only the drivers side fan runs. Did a test of the multi plug (relay) and it passed all fans ran at right speed and together as per instructions so the wiring to the fans is ok. The car also has i believe a thermal switch in the radiator not tested it yet As we know both fans should only ever run together So if any body has any ideas as to what to check and what could possible be at fault pleeeeese feel free to let me know. Many thanks Marko |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by wudz on Apr 15th, 2005, 5:11pm Hi Marko, I have seen the Fan diagram on the site, but try as I might to find it again I draw a blank...I am sure someone will know where it is..All I can remember is that the fans start up in slow mode..they are switched in series, 6v across each fan..tehn if the temperature still rises they are switch in parallel...bothe running fast with 12v each...It would seem that the one of therelays involved would be the problem or each fan may be independantly fused, if so this would be the problem as both fuses if OK would let both fans run slow and both fast...If one fuse blew then there would be no slow running on any fan and only full speed on one...but all this is from memory..the diagram would put you right if found... Best of luck John |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by nitram on Apr 15th, 2005, 5:30pm The wiring diagrams are here - http://www.carsoft.ru/avtorepair/sierra_el.html The diagram for your car is here - http://www.carsoft.ru/avtorepair/sierra/engcntrl25d.pdf. It does look on page 15 as if there is a 30A fuse directly behind one fan, and a 50A fuse behind the relay. My guess from what's been said is that the fuse marked F39 in the diagram is blown. |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by marky on Apr 15th, 2005, 7:51pm Thanks guys for the input , I am not very electically minded at all but the non running fan will run if i force 12v to it ,and also i connected pins in the relay multi plug with a wire to simmulate running conditions and they both ran as they are supposed to so with that i thought the fuses would be ok is it possible that they could be shot and still achieve the results i got ? if so i will try to find them and check them out |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by marky on Apr 18th, 2005, 2:23pm Does any one know how to test the thermal switch and is it removed easly? |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by Snoopy on Apr 18th, 2005, 2:47pm If it is the same as the 12v the one that fits into the side of the radiator then it jst twists off. It has a rubber seal and that may need to be renewed if you do remove it. It can be seen in item 6 on this page if that helps http://www.fordscorpio.co.uk/manual/cooling/TDCoolRad.pdf |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by wudz on Apr 18th, 2005, 10:05pm Hi Marky, In older cars the thermal switch was a bi-metal switch which when hot closed and either provided 12v to one contact of the motor, the other motor contact was fasten to the car body,,..or it switched the earth wire and 12v was always present on the motor..either way the fan came into operation until the cooled radiator opened the switch to turn off the fan... All that said I would think, knowing the Scorp that the thermal switch was conected to the PCM module and may be a PTC or NTC thermister and not a switch in the true sense, so shorting it out may not be a good idea as you could to test the old type....but I may be wrong. You could measure the resistance and put an hair dryer over it to see if it switched or varied its resistance..crude but may help you trace your problem...It still looks to me to be a fuse problem, because one of your fans is working and I would imagine that the thermal control would work both... Best of luck John |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by wudz on Apr 18th, 2005, 10:37pm Hi again Marky, Just had another look at the diagram Nitram posted and the relay on the far right must be the problem if or should that be a big IF... 1) you have no slow running on both or any fan. 2)the fan that works is Fan 1 ( upper most on diagram) 3) wiring back to fuse/ relay box is OK..which I think you have already proved to be OK.. The far left relay is the full speed relay for FAN 1 which is OK ( If that's the Fan that is running OK) The same control voltage operates the far right relay for full speed on FAN2 this fan does not work...faulty relay or wire from it to fan.. Center relay is the slow running relay power is supplied through the same fuse which works the good fan and is used in slow run mode for powering Fan2 (both in series), but no fans work in this mode because either the far right relay as stated is faulty or again the wire from it to Fan 2.. i,e. no path to earth for the good fan to work... Hope this clerifies your problem or at least helps.. Cheers John PS there is a better diagram on site but as said previously I can not find the blighter... |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by marky on Apr 19th, 2005, 7:35pm Thanks Snoopy and John It is proving very difficult to find the problem as all test so far have proved posotive but will be looking at the thermal switch next to try to test and sum up all that we (i) know. Thanks again John Accrington who is that near Chorley |
||
|
Title: Re: cooling fan( Electrical help )reqd Post by wudz on Apr 19th, 2005, 9:46pm Hi Marky, I still think the relay area is the problem, but it would more than likely be a poor connection in the relay socket rather than the actual relay at fault. I would be pretty certain that the internal spade connector to the none running fan in the relay socket is being pushed down or has fractured and therefore misses its connection to the relay when pushed home, but may work ok when a wire is pushed in to it to test the fan as you did.... double check this connection.. You could wrap a thinish wire around the associated tag on the relay and when the relay is pushed home poke the end in the under side of the socket or take straight to the fan ..... The diagram does not show the thermal switch used in direct control of the fans. The fans are directly controlled by the PCM via the relays therefore it seems that the PCM get's the Thermal switch information.. Yep, the very same Accrington nearish too (about 12mls) Chorley...not Adelington though,, Cheers John |
||
|
Ford Scorpio Forum » Powered by YaBB 1 Gold - SP 1.3.1! YaBB © 2000-2003. All Rights Reserved. |