Aircon switch blows fuse for airbag light

[id101]

Has anyone had this problem? If I switch on the aircon in my z3 3.0i it blows fuse 43 (7.5 amp) same happens if I leave the aircon switch on and I swap out the fuse and switch on ignition it blows.

Any thoughts?

Cheers in advance

 

[Zephyr]

short circuit, probably humidity, or bad fuse box (wires deteriorate with time and heat - thank you BMW for tour biodegradable wires, the planet is safe now)
do you have any after market electrical in the car?

 

[id101]

short circuit, probably humidity, or bad fuse box (wires deteriorate with time and heat - thank you BMW for tour biodegradable wires, the planet is safe now)
do you have any after market electrical in the car?

There's a different stereo in there that's about it

 

[Zephyr]

the internet may be wrong, but fron what I see, in the 3.0 model fuse 43 is a 5A.
What does your chart under the fuse box cover say?

 

[id101]

View attachment 293807
the internet may be wrong, but fron what I see, in the 3.0 model fuse 43 is a 5A.
What does your chart under the fuse box cover say?

Sorry my mistake it was fuse 41 a 7.5 amp one.

 

[janniczk]

It maybe:

• Shorted AC Compressor: A short circuit within the compressor coil can overload the circuit and blow the fuse.
• Faulty Blower Motor: If the blower motor seizes or has internal damage, it can draw excessive current and blow the fuse.

 

[Zephyr]

The AC system works as a backup. So better check the motor for your electric auxiliary fan motor, it may be seized.
Or theres an issue at the two relays (a high speed and low speed) that control the whole system.

 

[id101]

Interesting as I seem to remember the electric fan being on all the time but I don't think it is now

 

[Mint]

If you are chasing an electrical fault you may find this useful...

BMW Z3 - 2000 Z3 & Z3M Electrical Troubleshooting Manual for Great Britain

An Electrical Troubleshooting Manual Specifically for 2000 Z3 and Z3M cars in Great Britain. It includes the interior movement sensor used in the DWA security system.

zroadster.org

 

[Rudyrov]

I followed that link above and didn't see a manual, so here is the one I have.

 

[id101]

I followed that link above and didn't see a manual, so here is the one I have.

Cheers that's excellent, I won't understand it but i can always ask someone who does! Lol

 

[Rudyrov]

Cheers that's excellent, I won't understand it but i can always ask someone who does! Lol

IMHO- BMW's circuit diagrams and presentation style for these are very difficult to understand and follow. I would love to see a more conventional diagram or diagrams. What I do is print the various pages that connect the circuit I am trying to trace or sketch out what I see so I can look for a fault.

 

[Mint]

I followed that link above and didn't see a manual, so here is the one I have.

The download button is at the end of the title...

 

[Rudyrov]

The download button is at the end of the title...

Sorry about that, I had no clue that it was in that position on the page.
Thank you!

 

[Mint]

Sorry about that, I had no clue that it was in that position on the page.
Thank you!

Easy to miss