Golf IV - Climatronic not working - Fuse S180

Hello everyone,

Last Sunday (it was very hot), my Climatronic system failed while I was driving.
The problem was that the compressor failed to start in auto mode (the engine speed remained constant --> no cooling performance). I recently had the air conditioning system serviced, so I know that the system is leak-free.
Because of this, I browsed the forum and, based on the experiences reported by other users, I wrote down the possible causes of the problem.
In the Climatronic diagnostic menu, there were no error codes stored, and I couldn't figure out the compressor shut-off conditions. About 2 months ago, I had a similar problem that resolved itself after I checked and re-inserted all the Climatronic-related fuses. Today, I checked the fuses again, and I noticed that fuse S180 (30A, located on the far left of the battery) appeared to be burnt. I replaced it with a new one as a precaution. I've read in various posts that this fuse is linked to the fan, and if it's defective, the fan won't start, which in turn prevents the compressor from starting. After the change, I kept the Climatronic system on the "LO" setting, the fans were running, and therefore the compressor was also running. Cooling performance was also present.

"I don't understand why this fuse is melted but not blown (I tested it with a multimeter to check for continuity). If there's a defect somewhere in the wiring harness, or if the fan is drawing more current than usual due to an unforeseen overload, shouldn't the fuse blow instead of just melting?" The fuse holder on the battery is also slightly corroded.

What could have happened here? Is the fuse too slow and not blowing quickly enough?

I'm going to try uploading a picture of the fuse.

Regards,
-Chip-

Common issue. Replace the fuse holder and everything should be okay again. This happens because the fuse contacts may not make perfect contact after several years. This can occasionally cause a spark at the contact in the climate control system, which can eventually damage the fuse and its holder.

TDI-GTI-4-Motion wrote:

Known issue. Replace the fuse holder and everything is OK again. This happens because the fuse contacts may not make perfect contact after several years. As a result, occasionally a spark will occur at the contact within the climate control system, which will eventually cause the fuse and holder to char.

That was a really quick response. Thank you very much!
Did I just create a double post? I couldn't find anything about this in the forum.

I believe the holder is only available as a complete unit, or including the bracket for attaching it to the battery.

-chip- wrote:

I believe the holder is only available as a complete unit or including the bracket for mounting it on the battery?

No, it's without the support bracket. I think it costs around 45€, if I remember correctly.

I've been using the new fuse holder for about 2.5 weeks now, and so far, the air conditioning hasn't failed once. The fuse is still in good condition...
Let's see how long this lasts...