Advertise on fullfatrr.com »

Home > Technical (L322) > TD6 blowing fuse 39
Post Reply  Down to end
Page 1 of 1
Print this entire topic · 
John22000



Member Since: 25 Apr 2019
Location: Manchester
Posts: 5

United Kingdom 2004 Range Rover Vogue Td6 Zambezi Silver
TD6 blowing fuse 39

Evening everybody…

I have a very strange issue with my 2004 TD6 that has me completely baffled.

Each time the ignition switch is turned to position 2 (just prior to cranking) fuse 39 goes pop. The car subsequently will then not crank.

I’ve had a poke about today and found that if you turn the key to position 2 without a 5amp fuse in slot 39, then put in the fuse it stays intact and the car starts and runs normally.
Suspecting the ignition switch I’ve had the center console out and the ignition switch out to check and clean the plug and look for any possible damaged wiring, I’ve not tried dismantling the switch as there is a big looking spring in there to return the switch to pos 2 after cranking and with my luck this would disappear somewhere never to be seen again.

What’s confusing me even more now is the fact that the fuse only blows if it’s in place when the key is turned, surely if there was a short somewhere it would go as soon as it’s inserted, all I’m doing by putting the fuse back in when it’s already in pos 2 is moving the point of contact from the switch to the fuse aren’t I ….?

It did have a replacement switch a couple of years ago, symptoms were very similar fuse 39 blowing but it only happened intermittently and would be fine for a while with a new fuse.

A new switch isn’t cheap and I’d rather have a little bit more certainty that this could be the issue before I take the plunge and order one up.

Anyone have any suggestions or opinions, anyone had a similar issue?
I can find similar threads but nothing relating to fuse 39 blowing

Cheers,
John

Post #620093 15th Jan 2022 6:01pm
View user's profile Send private message View poster's gallery Reply with quote
nicedayforit



Member Since: 11 Jun 2011
Location: Beside the Solway
Posts: 3951

England 2004 Range Rover Vogue Td6 Giverny Green

Fuse 39 protects the steering lock ecu.Why it should blow in the manner you describe l have no idea but it’s a start. Thumbs Up

Post #620114 15th Jan 2022 8:28pm
View user's profile Send private message View poster's gallery Reply with quote
nicedayforit



Member Since: 11 Jun 2011
Location: Beside the Solway
Posts: 3951

England 2004 Range Rover Vogue Td6 Giverny Green

If you click on Wiki at the top right of the page and go down to INFO you will see electrical circuit diagrams.
Go to pages 30 and 32 of the diagrams and you will find what fuse 39 does. Thumbs Up

Post #620117 15th Jan 2022 8:49pm
View user's profile Send private message View poster's gallery Reply with quote
John22000



Member Since: 25 Apr 2019
Location: Manchester
Posts: 5

United Kingdom 2004 Range Rover Vogue Td6 Zambezi Silver

If I’ve been reading the circuit diagrams and the system description and operation manuals correctly fuse 39 seems to cover the auxiliary feed to both the steering lock and immobiliser ecu’s.

When the key is put into the switch the steering lock can be heard to click and disengage, when the key is turned all the dash lights come on, the steering wheel adjusts to the driving position, radio comes on, blower starts etc….in short everything seems to be absolutely fine until the second position, when the fuse blows.

All of the above are not effected, dash, stays lit, blower still runs, radio stays on but the car won’t crank with the fuse blown.

Just for an experiment I stuck in a 10 amp fuse instead of a 5 amp and this still blows, didn’t fancy going higher than a 10 amp.

It’s got me well and truly stumped. Even if there was a high resistance in the ignition switch this should reduce the current wouldn’t it?..

Post #620126 15th Jan 2022 10:38pm
View user's profile Send private message View poster's gallery Reply with quote
AJGalaxy2012



Member Since: 11 Jun 2018
Location: Gainsborough
Posts: 1446

United Kingdom 2012 Range Rover Vogue SE 4.4 V8 Bonatti Grey

A high resistance would reduce the current as you say, it does sound to be a really odd issue. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

Post #620131 16th Jan 2022 4:17am
View user's profile Send private message View poster's gallery Reply with quote
nicedayforit



Member Since: 11 Jun 2011
Location: Beside the Solway
Posts: 3951

England 2004 Range Rover Vogue Td6 Giverny Green

The only thing the second position on the switch operates is the starter circuit. Given that everything is ok until you go to the the second position it does suggest that the earth fault is associated with the starter circuit. This is more so as when you start the car without the fuse and then put the fuse back in everything is ok ie the starter circuit is out of circuit.
I’m guessing that there is an earth fault somewhere on the starter circuit. Could it be simply a case of one of the wires chaffing?

Post #620137 16th Jan 2022 9:07am
View user's profile Send private message View poster's gallery Reply with quote
John22000



Member Since: 25 Apr 2019
Location: Manchester
Posts: 5

United Kingdom 2004 Range Rover Vogue Td6 Zambezi Silver

Made progress but I honestly don't thing it the end of the saga..

I studied the wiring diagrams, looking in particular at the power distribution section on pages 11-15, Fuse 39 should only become live when the ignition is turned to AUX (position 1), it does and the fuse does not blow. When the ignition is switched to IGN (position 2) Fuse 39 blows so I went looking for somewhere that had feed from both.

On page 13 I found the seat relay had a possible link through something called relay 6, no idea what this is couldn't find it, don't even know if it exists and I'm sure its drawn wrong on the diagram but I thought with nothing to lose I'd have a look for the seat relay. Found it, buried behind the glovebox, took it out, looked at it, cleaned the terminals, put it back in, turned the key to AUX, crossed my fingers, turned the key to IGN and would you believe the fuse doesn't blow. Cranked the engine, car starts...

Tried it a good few times just to be sure and it seems to be OK

Now I have no idea why this may have caused the issue I was having and like I say I very much doubt that this will be the end of it. But for the time being at least the car starts and there are no flashes from the fusebox......... Very Happy Very Happy

Hope its still fixed in the morning.

Does anyone else find the Wiring diagrams so difficult to follow...?
Back in the day everything was so much easier....!!

Cheers for the help

Post #620231 16th Jan 2022 6:39pm
View user's profile Send private message View poster's gallery Post Reply
Post Reply  Back to top
Page 1 of 1
All times are GMT

Jump to  
Previous Topic | Next Topic >
Posting Rules
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum



Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
fullfatrr.com RSS Feed - All Forums


Switch to Mobile site