Guys, is it normal that my radiator fan never switches on and temperature needle is always in the middle (normal temperature). Recently I replaced my radiator fan because older one on my skoda was pretty much stuck and had burnt plastic smell (I realise that few day ago when it was really hot outside) and then I replaced my fan/temp switch, even though older one, as I said, showed normal temperature I thought it might be broken and could be reading bs but as it seems it is not the case. I never seen my temp climb over 90 degrees even while sitting in traffic on hot day for 15mins and fan never kicks in... Is there a problem or these older skodas use radiator fan if temp is going over normal ? Thanks !

I forgot to mention fuses were fine and whole fuse box on battery seems to be in good shape.

Hi, Welcome to Briskoda.

 

What model Octavia is yours?, do you have aircon/climatronic fitted?.

2 hours ago, kentphil1 said:

Hi, Welcome to Briskoda.

 

What model Octavia is yours?, do you have aircon/climatronic fitted?.

Thanks for a warm welcome ! I have skoda octavia mk1 year 1999 without an AC. I read some more and some websites say that it could be thermostat's fault, when it is stuck open engine never even gets to right temperature where it should be so I might have found my problem. Although it does not make this fix easier haha

Which engine size is your octavia, is it petrol or diesel?. 

 

Sorry for the questions, but a little info now can make diagnosis a bit easier and closer.

 

A 3 letter engine code - i.e. AUM, BKE etc will make it much easier if you know it.

8 hours ago, kentphil1 said:

Which engine size is your octavia, is it petrol or diesel?. 

 

Sorry for the questions, but a little info now can make diagnosis a bit easier and closer.

 

A 3 letter engine code - i.e. AUM, BKE etc will make it much easier if you know it.

Oh forgot to mention it is 1.9 TDI 66kw it does have a remap done to 90kw but same problem was way back I assume because fan could have been stuck for months.

When you say you replaced the fan temp switch, would I be correct in assuming you mean the one in the radiator?.

 

I seem to recall from memory that the diiesel non air con cars have a fan relay in a box under the bonnet, have you checked that item at all?, perhaps one of the diesel owning chaps on here could confirm this, as it has been a while since i've looked at a diesel in anger.

 

Also, the blade fuses in the battery fuse box can have a habit of fracturing and looking ok, when they actually are blown. a quick check with a multimeter or fit a good spare is your way forward there.

 

How does your temp gauge read on the road?, does it reach 90 degrees and sit there or does it drop back going down hills?.

 

Unplug the loom connector from the radiator thermoswitch and test for 12V at the connection fed by the red wire, that comes from a 30amp fuse on the battery.

If that's there, you can test both speeds of fan operation by linking that connection to each of the others. If you link to the red-white connection, it should come on at low speed, move it to link red to red/black and full speed should happen.  Mind hands/fingers and expect a spark when you link the pins.

 

The above should be able to trigger both speeds even if the relay mentioned above isn't doing anything. That relay lives in location 13 of the cabin relay holder, if my understanding of the wiring diagram is correct.

Edit, relay only fitted to AHF engine code apparently, I think yours is AGR?

Edited 13 June, 20205 yr by Wino

37 minutes ago, kentphil1 said:

When you say you replaced the fan temp switch, would I be correct in assuming you mean the one in the radiator?.

 

I seem to recall from memory that the diiesel non air con cars have a fan relay in a box under the bonnet, have you checked that item at all?, perhaps one of the diesel owning chaps on here could confirm this, as it has been a while since i've looked at a diesel in anger.

 

Also, the blade fuses in the battery fuse box can have a habit of fracturing and looking ok, when they actually are blown. a quick check with a multimeter or fit a good spare is your way forward there.

 

How does your temp gauge read on the road?, does it reach 90 degrees and sit there or does it drop back going down hills?.

 

I actually replaced fan/temp switch that sits on the right side of an engine. I've seen these fans switches that go on radiator but for some reason did not take a look, will definitely have to do that too. These skodas do have fan relay under the battery and it looked good but it's hard to say if actually it works.

 

About fuses, I checked them all with a multimeter and on every fuse was fine and legs weren't corroded.

 

My gauge needle slowly climbs to 90 (5mins in summer and about 10-15 mins in winter) and it kind of stays there all the time, even with my older fan/temp switch gauge needle wasn't jumping or reacting to speed like hills that you mentioned.

6 minutes ago, Wino said:

Unplug the loom connector from the radiator thermoswitch and test for 12V at the connection fed by the red wire, that comes from a 30amp fuse on the battery.

If that's there, you can test both speeds of fan operation by linking that connection to each of the others. If you link to the red-white connection, it should come on at low speed, move it to link red to red/black and full speed should happen.  Mind hands/fingers and expect a spark when you link the pins.

 

The above should be able to trigger both speeds even if the relay mentioned above isn't doing anything. That relay lives in location 13 of the cabin relay holder, if my understanding of the wiring diagram is correct.

Thanks for these tips, will definitely have to try them out too.

Is the relay you are refering to the rectangular fan control unit and bolted on below the battery?, as I thought that was only fitted to vehicles with air con, or has it only got one connector going to it rather than the normal 2?. I have had to renew this unit due to failure in the past, but the procedure that Wino listed should check that unit out if you have one fitted.

 

I was refering to an openable box that has the relay inside it, from memory, i think it was to the side of the battery, but it is nearly 9 years since I last looked at a diesel 90 bhp, so I may be wrong.

 

The switch on the radiator is the thermal switch, I believe the other one is a thermal sender for the gauge.

Edited 13 June, 20205 yr by kentphil1