Blowing 5 amp fuse on measuring circut

[jcdub]

Got this sorted

Edited 6 June, 2012 by jcdub

[patrolman]

I need your help guys. My 08 octavia rs cr blew a fuse in the engine compartment yesterday throwing up all sorts of lights on the dash. Found the problem a blown 5 amp fuse for the measuring circut, F4 on the panel. I replaced it with a New fuse 5 amp of course. And all was well. I tool the exact same journey today and at roughly the same point the warnings came on again. I pulled over and checked the fuse and it was blown. I had spares this time and I replaced it with a 10 fuse and continued my journey with no more faults. I'll be bringing the car into Skoda on Monday to have this checked out. What does the measuring circuit measure?

In the owners manual it shows 2 types of fuse boxes, same design different layout. The thing is, mine hard version 2 in the manual but the fuse for the measuring circuit in the position F4 on version 1 bou this is where my measuring fuse is.

So can someone send of a pic of their rs cr fuse box showing the fuse positions. This would really help. You can email me at [email protected] if you can take one and send it.

Hope you can help.

If i was you i would take the 10 amp fuse out right away,its 5 amp for a reason what cauld be somthink small may be come a mager problem if the circuit overloads !

[jcdub]

If i was you i would take the 10 amp fuse out right away,its 5 amp for a reason what cauld be somthink small may be come a mager problem if the circuit overloads !

Will be doing that before my journey home. Looking for the pic of the fuse box with fuses showing though...

[jcdub]

Anyone have a pic of their engine fuse box showing fuses on their cr rs tdi?

[jcdub]

Quick update. I bought a few 5 amp fuses today. I drove the are and the fuse blew again, and then again. It always happens at exactly 12kms every time. What ever the car is doing / checking its causing the fuse to blow. Any ideas? Its going into Skoda on Monday either way:(

[j3ggo]

Does anyone know what the measuring fuse is for?

[Breezy_Pete]

Possibly a battery voltage sensing feed. If you tell me fuse number & location, plus year car was made and engine code, I can try to look it up.

[j3ggo]

Possibly a battery voltage sensing feed. If you tell me fuse number & location, plus year car was made and engine code, I can try to look it up.

its F3 in the engine compartment version 2. 2009 Octavia 1.8TSI CDA engine. Thanks

[Breezy_Pete]

Yep,  on your car it's a wire going only to (pin 24 of) J519 Onboard power supply control unit (better known as BCM, I think) direct - or as directly as possible with a fuse for wire protection - from battery positive.  Can't be 100% sure without seeing inside the J519 unit, but an analogous wire on my Polo and the missus's Fabia goes to circuitry inside that looks exactly like what I'd expect for voltage measuring.  If any non-dedicated wire was used instead, the voltage measured would depend on what other currents were flowing. With a dedicated wire, you get the best possible 'view'.

On ours there's also a dedicated thin brown earth wire going right from the negative battery clamp to another pin of J519.  Doesn't look to be present on Octy2, the equivalent from pin 23 of J519 goes to an earth connection point in the cabin loom.

 

On cars with start/stop the Fuse 3 wire also goes to the battery monitor control unit, which kinda confirms it IMO.

Edited 23 December, 2016 by Wino

[j3ggo]

The fuse had blown in my Octavia. Not sure why? I am in the process of fitting a new rear wiper motor. When I get the arm off!

[Breezy_Pete]

Could be that someone has added something aftermarket to that feed by scotchlock or similar under the dash, and that something is drawing more than 5 amps. Worth a look to see if something has been spliced into a red/lilac wire going to pin 24 of a 52-way connector at J519, if access to inspect isn't too bad.  'Fraid I don't know where exactly to look on an Octy2, but close to cabin fusebox above accelerator pedal on cars I'm familiar with.

[meaty101]

Is that what's happened. I wondered where the quote came from!! Poor form imho asking for help then not informing the whole forum what the problem was.

[erindad]

Am I missing something here or is it a time warp ?

 

An old post from 2009  edited 2012 . by jcdub ?

 

Lucky if he still has the car , if he has its probably sorted now  ( I hope). ,if not  it may have been burnt out by now

 

or maybe too much Christmas cheer ?

Edited 25 December, 2016 by erindad

[meaty101]

Jcdub was on here just under a month ago so they are still an active member. It's not the issue with the car, after all this time I'm hoping it's fixed. It's the fact they've been asking for help then never posted back what the fix was. It isn't very helpful really is it.

Edited 25 December, 2016 by meaty101