Hello,

 

Firts of all, I'm sorry for my english.

 

Well, I have an Octavia TDI AGR from 1997.

 

Three weeks ago, the fuse box on top of the battery was burned. I ask for a replacement, and replaced it. I checked all the fuses and were ok.

 

But the issue is that since the fuse box was damage, that the fans are performing in a unusual way. If I drive with the AC on, the fans don't stop till I switched the engine off, althoug I had stopped the AC minutes ago. The engine temperature doesn't goes beyond 90ºC. If I switch on the engine a few hours later, say 5-6 hours, both fans start running, but engine temperarute is low. If I switch the engine the next day, it doesn't do it.

 

Also, when the engine reachs around 94ºC the first fan starts. 

 

If I don't use the AC, then the fans are not running continously.

 

Does anybody know what could be the cause? The fan controllor unit?

 

Regards,

Edited 18 July, 20196 yr by adelgadom

These are prone to fan relay issues. Being as it’s 22 years old it wouldn’t surprise me if this was the issue. You will need to get one with the exact part number though. There is also a fan switch in the radiator that could also be the issue. You could also get vcds diagnostic software plugged in to check the coolant is up to temp. 

Hope some of this helps?

Hi,

 

I've passed vcds and there are not errors.

 

I didn't know about the switch in the radiator. Where is suppose to be, at the top, bottom?

 

Thanks,

By the bottom

hose

Just the top of my head, for a burnt fuse box. Double check the resistance back to the battery. I had this issue and the black wire had to be replaced. From there you can continue to fault find.