Fans problem - please help diagnose

[007]

I can't really help you, except to relate my own tale of woe about fans. Misery loves company and all that!

Like yours the fans on the beetle would never turn on no matter how hot the engine was, except when the aircon was on. With A/C on the fans would run at low speed (as they should), until the car got hot, and then they would switch to high speed for a few seconds and then switch back down to low then pulse up and down. I read all the posts and ended up replacing everything, fan control module, radiator switch and the other two temp sensors the turbos have in the hoses. But nothing fixed it. So I drove it around with the aircon on all the time to avoid cooking the motor and I was contemplating replacing the fans themselves. Because I didn't know what else to do.

Then one day I was driving home and turned the aircon off. Straight away there was a crack like a fuse giving up and the smell of electrical bits cooking and my instrument cluster died. The car continued to run as normal so I drove it home and into the garage. Popped up the bonnet and the first thing that happened was the fans came on (without the aircon!). The fans worked perfectly on high and low speeds from that day on. All the other electrical bits and pieces worked as normal and no fuses had blown.

I've had the instrument cluster repaired and everything is good, but I haven't turned the aircon back on, as I now suspect the A/C switch might have been the problem all along.

I'm working overseas at the minute and I won't get a chance to test/replace it until I get home at Christmas, but the more I think about it, the more I think the problem with my fans was an A/C switch/relay problem. If worse comes to worst, I'll just live without A/C!

Good luck with yours, I know how frustrating it is and I hope you get it sorted soon.

[Bora Sport]

I hope I am not stating the obvious here but if your refrigerant gas level is too low then the aircon will not turn on either because of the low pressure switch. Also there is a fuse on top of the battery that used to blow on my Bora. The aircon would stop and all that was needed was to replace that 25amp as I recall, fuse.

[PranK]

Holy smokes! Thats awesome and scary and crazy and totally VW. I love it!!

Thanks for sharing!

[PranK]

I hope I am not stating the obvious here but if your refrigerant gas level is too low then the aircon will not turn on either because of the low pressure switch. Also there is a fuse on top of the battery that used to blow on my Bora. The aircon would stop and all that was needed was to replace that 25amp as I recall, fuse.

Correct, low pressure will stop the fans, but will it stop the compressor?

Can I test low gas without getting more gas? Ie, will an error code log?

[Snail Style]

If the high pressure switch is a 3 pin, then you should be able to check the system pressure with that. Otherwise you need to have someone put some gauges on it to see what is going on.

[PranK]

If the high pressure switch is a 3 pin, then you should be able to check the system pressure with that. Otherwise you need to have someone put some gauges on it to see what is going on.

How would I do that? Same as the thermo switch? Bridge the terminals and see if things start working?

[Snail Style]

Vcds measured value blocks

Sent from my HTC 2PS6200 using Tapatalk

[PranK]

Vcds measured value blocks

Sent from my HTC 2PS6200 using Tapatalk

I'm sorry but I don't know how to do that.

[PranK]

Well, a positive update.

I had a mobile A/C guy come over on Saturday. He found a big leak in the A/C which he fixed but when we added gas to the system the pressure switch just kinda fell apart. He was carrying a spare switch which he fit.

Once it was gassed up my fans worked! Yahoo! So, I have fit the resistors mod to the fans while the front is off and everything is working a charm.

Thanks all for the help!

Christian

[JustCruisn]

Nice result.
You might want to just get a new fan, I did mine for under $100 takes about 15min to replace, 3 screws and an electrical plug.