Jump to content

Electric Rad Fan Conununundrum


Recommended Posts

Saturday afternoon I pop out to the fuel station to top up for the TSSC New Forest run yesterday.

When I got home I noticed that the temp was very high and the fan hadn't come on.

No problem I'll just flip the override switch. Sadly it was a problem as that had no effect either.

So I gave it one of my looks and lo and behold it started working.  Didn;t have much time to play with it so I put it down to a gremlin.

On the run I had no problems but I occasionally flips the override and found it was not working.

What can possibly go wrong !!!!!

The fan could die, but would it recover every now and again.

The thermostatic switch in the pump down pipe could could go duff but the override switch would eliminate that.

The override switch could go duff but the thermoswitch should eliminate that. Could they both go duff together - ooer!!  But the switch made the warning light come on.

So, firstly swap out the relay - no joy.

Check the continuity of the wiring - what wiring - where is the wiring diagram.

OK - after a great deal of messing about I found a wire common to the thermo and  override switch that should pull the relay coil in was not behaving it self.

I could only get to the ends of the wire as it was hidden in the loom. The ends were fine, so there must be a break internally along its length.  Could there be a failed splice in there.!!!

It can't be burnt out - 100mA coil with 8 Amp wire - no way.

So I now have a working fan (for how long !!!) with a piggy backed repair wire. AND a wiring diagram.

I wonder what tomorrow will bring

 

Roger

 

 

 

 

Link to post
Share on other sites

HO! Could you come and give my window lifts a serious look please? Alternatively do your looks work over Skype?

QUite possibly the break in your wire is at a stress point, ie just inside the insulation near the connector, you could try taking an inch or so off and soldering [in a new length] and connector. Or just wrap your new wire into the loom, that would make a fix into a repair :)

Mike

Link to post
Share on other sites

Hi Mike,

    sadly my 'look' has no lasting powers. Having replaced what was an open circuit wire with a wire that made it work it has stopped working today.

So tomorrow I shall take it apart and see what is going on.  I fear it may be the actual fan.

 

Oh Dear

Roger

Link to post
Share on other sites

Could be an earth issue which would be common in both systems. 

Link to post
Share on other sites

Hi Folks,

    Just come home around the M25 with no fan :o:o - thankfully no jams (miracle).

With the override switch ON. I waggled the two pin plug/socket coming form the fan - Lo & Behold the fan came on.

So it is something to do with the connector (probably) 

Interestingly the earth return wire, from the thermo switch, has a 39 ohm resistance compared to the Neg post on the battery.!!

more investigation to do.

 

Roger

Link to post
Share on other sites

Hi Roger, I had a similar problem a few years ago and although my solution does not appear to be the same as yours I will repeat it anyway in case it helps someone else. 

I cured my problem by removing the Ammeter and cleaning the connections on the back, what was happening was corrosion was causing high resistance and the ammeter could not pass enough current to run fan and overdrive solenoid. Has never been a problem since.

Chris

Link to post
Share on other sites

New day fresh brain.

It is now all working again !!!   I could not find any positive issue. The connector block (push on spades) looked grubby so that was cleaned and a squirt of 'Servisol' cleaner.

I don;t understand how the first red wire that I found 'open circuit' was actually OC. But I measured it a number of times.

All very odd.

I shall run it up on the drive and thermo to switch in and see what happens.

 

Roger

Link to post
Share on other sites

Hi Andy,

 that was the process I was working down.

I think I have cracked it now :o  corroded connector feeding the fan (+12v and earth).

 

I'm sure I'll be out there tomorrow fixing it again.

 

Roger 

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.