Cruising Vs Stationary Water Temp Readings (Pics)

[Ams 23 1 Cars]

I would short the wires on the plug but the fan on high speed sounds like a dozen hoovers! It actually stays on for a little while if I switch the car off (keys out) while it's already active. Not sure if this is normal either.

 

Welshpug PM'd

[Anthony 1,003]

Yes, it's normal that it will keep running with the ignition off - it's completely seperate from the rest of the car electrics, on its own little seperate subloom.

[Ams 23 1 Cars]

Ah good, one less thing to worry about.

[Ams 23 1 Cars]

I fitted the resistor today (cheers for that Welshpug ) but unfortunately nothings changed with how the fan behaves. I think it's possible the contacts inside the plug are too corroded. The pic below shows the rather rough condition of the contacts (the three pin thing is just the resistor):

 

 

 

I cleaned it as much as I could with contact cleaner but it remains as shown above. The fan doesn't budge until the temp gauge is sitting pretty high as shown on Page 1 . Is it possible the general wiring has been cocked up or should I replace the plug and then try again?

[TooMany2cvs 65]

OK, step by step, because it makes this guesswork utterly simple.

 

First off, take the plug off the sensor and find which one's the live feed.

 

Now get a bit of wire, and jump between that and first one then the other of the other two terminals.

 

Are both speeds working?

 

Yes - it's the sensor.

No - time to dig into the one that isn't.

Take that +12v feed, and jump to the "before" end of the resistor. Does it work? Yes? It's the wiring between the plug & resistor.

No? Now jump to the "after" end of the resistor. Does it work? Yes? It's the resistor.

No? Now jump straight to the fan terminal. Does it work? Yes? It's the wiring after the resistor.

No? It's the fan.

 

That simple.

 

It might be two problems, of course. If so, just repeat the whole series of steps in an organised fashion until everything works. You'll just identify the problems step-by-step back from fan to sensor.

[DanteICE 72]

To eliminate a bad resistor (not saying it is, just removing any variables from the testing) just connect the resistor plug up with some wire so that it makes a circuit.

 

Basically try to remove as many variables as possible; so straight wire the thermoswitch so that you can control which fans are on and then wire past the resistor.

 

Get a little piece of high grit sang paper and slide it in and out of that plug using a flat electric connector as a backing (wrap it over the flat end so that it stays straight).

 

Maybe it's time to invest it a good multimeter? I got a good draper one for about £20, it's paid for itself when I had to fix my fans and side indicator lights. Helps you very quickly locate the bad connections without having to take much apart.

 

Geoff

[DanteICE 72]

OK, step by step, because it makes this guesswork utterly simple.

 

First off, take the plug off the sensor and find which one's the live feed.

 

Now get a bit of wire, and jump between that and first one then the other of the other two terminals.

 

Are both speeds working?

 

Yes - it's the sensor.

No - time to dig into the one that isn't.

Take that +12v feed, and jump to the "before" end of the resistor. Does it work? Yes? It's the wiring between the plug & resistor.

No? Now jump to the "after" end of the resistor. Does it work? Yes? It's the resistor.

No? Now jump straight to the fan terminal. Does it work? Yes? It's the wiring after the resistor.

No? It's the fan.

 

That simple.

 

It might be two problems, of course. If so, just repeat the whole series of steps in an organised fashion until everything works. You'll just identify the problems step-by-step back from fan to sensor.

 

You b*st*rd! You got there first!!!

 

He is right though

[Ams 23 1 Cars]

Many thanks for the helpful pointers 2CV and Dante. Bear with me as I'm new to this but confident I can do it So before I get on with the checks listed above can you explain a little more on what you mean by "sensor" when you say "take the plug off the sensor and find which one's the live feed."? Do you mean the red band/blue plug Thermo Switch on the radiator (as pictured at the top of this page) or the "Cooling Fan Switch" highlighted below?:

 

 

I have a single fan though

Edited August 15, 2013 by Ams

[TooMany2cvs 65]

Do you mean the red band/blue plug Thermo Switch on the radiator (as pictured at the top of this page) or the "Cooling Fan Switch" highlighted below?

Whichever one of the two was used by whoever fitted the engine to your car...

[Anthony 1,003]

Ignore what's labelled as "cooling fan switch" in that picture - that's only for AC equipped 306/Xsara's that use the "Bitron" fan control system. It's completely redundant on a 205 GTi-6 conversion.

 

You want the thermoswitch on the radiator, as that's what controls the fan on 205's (and most other non-AC 90's PSA models)

[DanteICE 72]

Ignore what's labelled as "cooling fan switch" in that picture - that's only for AC equipped 306/Xsara's that use the "Bitron" fan control system. It's completely redundant on a 205 GTi-6 conversion.

 

You want the thermoswitch on the radiator, as that's what controls the fan on 205's (and most other non-AC 90's PSA models)

 

Agreed, the thermoswitch is on the radiator next to the nearside front lamp. It'll probably be surrounded by a rubber glove type cover to protect it. And when you remove it, you'll see 3 pins, in a triangular shape.

[Ams 23 1 Cars]

Excellent thanks for the clarifications. I'll get on it now.

[Anthony 1,003]

Agreed, the thermoswitch is on the radiator next to the nearside front lamp. It'll probably be surrounded by a rubber glove type cover to protect it. And when you remove it, you'll see 3 pins, in a triangular shape.

Earlier thermoswitches are like that, whereas later ones had all three pins in a line and no boot, as per the picture ams posted at the top of this page.

[DanteICE 72]

Earlier thermoswitches are like that, whereas later ones had all three pins in a line and no boot, as per the picture ams posted at the top of this page.

 

Ah yes good point. Well there you go matey, that image at the top of the page with the blue 3 pin plug is the thermoswitch, so unplug it and short two of the pins on the socket until you've worked out which is the main pin and which two are for high speed and medium speed (if that makes sense).

 

Is the main pin the middle one Anthony?

 

Geoff

Edited August 15, 2013 by DanteICE