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JOKER



Member Since: 11 Sep 2008
Location: Sconnie Botland
Posts: 15876

Scotland 
FBH Problem time

This morning it was a bit on the icy side when taking the dogs out , so thought i would hit the remote and fire up the FBH as i do the school run at 7.30 am , pressed the remote Green then flashing Green FBH kicked in then about 60 seconds later it stopped , tried again and just got the same scenario , looks like its a trip to the dealers for this i think ��..

Why do these Censored's always cause problems Rolling Eyes Rolling Eyes ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

Post #145468 9th Oct 2012 7:53am
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ebajema



Member Since: 24 Mar 2011
Location: New Plymouth
Posts: 4782

New Zealand 2010 Range Rover Autobiography 5.0 SC V8 Galway Green

The FBH doesn't like the Scottish weather anymore than you do ??? MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

Post #145478 9th Oct 2012 8:12am
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SteveMFr
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Member Since: 22 Nov 2009
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Re: FBH Problem time

JOKER wrote:

Why do these Censored's always cause problems Rolling Eyes Rolling Eyes

Cause it's a LR? Laughing Wait - is this a trick question?.. Shocked


Rolling with laughter

Actually, the FBHs are relatively reliable (they're German made.. Whistle ). You might've just had a bit of bad luck...

Have a read at this, Mick. Wrote this in response to an FBH thread below but it basically answers your question. BTW, JR has kindly let me know tha my old info on FBHs is... old. The flame sensor is no longer a photocell, rather resistance is measured at the glow plug. All other info is correct, tho.

If you'd a bought an IIDTool, it would now tell you what is bad... Cool
Rolling with laughter
JK - I hate pressure selling tactics


SteveMFr wrote:
JR's info is spot on.

The ignition sequence for the FBH is (exactly the same as an oil furnace, btw):

- glow plug pre-heat ~30sec. > fuel pump on ~5sec > combustion air fan on > flame sensor must detect a flame w/in ~5-10 sec or it automatically shuts down.


These times are very approximate and stem from when I used to work on these things over 15 years ago. I'm sure there is a service manual for the FBH floating around the net somewhere. There will be an accurate time line printed in that.

You can hear each of these steps (except for the glow plug heating, obviously :-p ): about 30 secs after the FBH is told to start the fuel pump can be heard ticking quietly (rear seat), and then the combustion air blower begins to whir (behind the RF wheel). If the FBH ignites, the whir will grow to a small jet-engine like sound.

The FBH is a very simple device and really does function just like a small oil furnace only that the fuel is not injected but rather metered exactly on to a membrane. The combustion air fan (or blower) also has to blow an exact volume of air through the membrane so that the mixture is correct. The glow plug ignites the mixture and the flame sensor (a simple photo cell) must report the presence of a flame w/in a certain time or the FBH shuts down as a precautionary measure before the fuel pump fills the FBH with unburnt fuel. Both the fuel pump and the combustion air fan are designed to meter the fuel / air exactly when the receive 12V and are otherwise more or less 'sealed units'. If they do not function properly, they must be replaced.

The most likely culprits in a failed ignition sequence are (from most to least likely):

- bad glow plug
- bad flame sensor (in this case you'd hear the FBH ignite as described above but it would then suddenly shut down)
- bad fuel pump (no fuel/too little fuel)
- bad combustion air fan (no air/too little air)

As my experience is based on working on FBH's in general and I have no experience working on exactly the FBH's in our RR's, I can not tell you how sensitive the ECU's are and how far up the likelihood ladder they should be placed. I can tell you that based on my experiences on working with auto electrics/electronics, ECU's are replaced far more often than necessary by technicians inexperienced on that particular vehicle system.

As the IIDTool is giving you a flame sensor fault, listen to the ignition sequence. If you can hear the whir grow to a (very small Razz ) roar after a couple of seconds and the FBH then still shuts down, this will be your prob. A new flame detector should not cost more than GBP20-25 max. The only other alternatives at that point would be the ECU or an even more rare wiring prob (short to ground in the flame detector wiring).

Please let us know what happens.
 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)

Post #145698 9th Oct 2012 9:33pm
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47p2



Member Since: 05 Oct 2010
Location: Gone Beyond, Subaru
Posts: 8048

Scotland 
Re: FBH Problem time

JOKER wrote:
This morning it was a bit on the icy side when taking the dogs out , so thought i would hit the remote and fire up the FBH as i do the school run at 7.30 am , pressed the remote Green then flashing Green FBH kicked in then about 60 seconds later it stopped , tried again and just got the same scenario , looks like its a trip to the dealers for this i think ��..



Man up biscuitbaws, wasn't even that cold this morning Whistle

Post #145708 9th Oct 2012 11:15pm
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northernmonkeyjones



Member Since: 24 Mar 2012
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United Kingdom 2016 Range Rover Autobiography SDV8 Santorini Black

Tried to fire mine up at the weekend Mick,

didnt work on the saturday, but after a few goes it fired up on sunday and is now firing up fine. Maybe they just need a bit of regular use.

Run a few stop start cycles and see if it lights. Mine was definately going as the flue gasses under the car were warm

Thumbs Up There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

Post #145721 10th Oct 2012 6:22am
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mzplcg



Member Since: 26 May 2010
Location: Warwickshire. England. The Commonwealth.
Posts: 4029

United Kingdom 2014 Range Rover Vogue SE SDV8 Corris Grey
Re: FBH Problem time

47p2 wrote:
Man up biscuitbaws


Rolling with laughter Rolling with laughter

Love that expression. A Glasgow lad used to work for me and there were quite a few variations on the "Baws" word, depending on the circumstances. Still PMSL recalling some of those.

Oh, you're right too. Man up Mick. You lads from Scotland aren't supposed to feel the cold. Even Rab C Nesbitt only ever wore a string vest Laughing

Post #145722 10th Oct 2012 6:35am
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IanV8



Member Since: 14 Jan 2010
Location: Dunfermline
Posts: 502

Scotland 2011 Range Rover Vogue SE TDV8 Santorini Black

Must be something in the air up here as mine won't fire up.

Car going in next week for warranty work so another one to add to the list.

Ian

Post #145724 10th Oct 2012 6:51am
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JOKER



Member Since: 11 Sep 2008
Location: Sconnie Botland
Posts: 15876

Scotland 
Re: FBH Problem time

47p2 wrote:
Man up biscuitbaws, wasn't even that cold this morning Whistle


Although we are only 8 miles apart up here in EK can be entirely different to your area on cold mornings bawbag ,

Anyhow it wasn't for me it was to try and heat the car up for the school run ya heidnipper Laughing Laughing ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

Post #145732 10th Oct 2012 7:46am
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47p2



Member Since: 05 Oct 2010
Location: Gone Beyond, Subaru
Posts: 8048

Scotland 
Re: FBH Problem time

JOKER wrote:

Although we are only 8 miles apart up here in EK can be entirely different to your area on cold mornings bawbag ,



Oh so toasty warm in my garage this morning fannybaws Whistle

Post #145743 10th Oct 2012 8:48am
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wackyjim



Member Since: 11 Aug 2010
Location: Brigadoon
Posts: 2015

Scotland 2011 Range Rover SE TDV8 Santorini Black

U west coast boys dinnae ken what cauld is!!!..up here in the north east when the wind starts soochin thats real cauld weather!! Laughing by the way my FBH is no working either Big Cry

Post #145745 10th Oct 2012 8:57am
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JOKER



Member Since: 11 Sep 2008
Location: Sconnie Botland
Posts: 15876

Scotland 

Surprised you haven't posted pictures up of your oh so wonderful garage as you normally do ya glaikit looking botten � Yawn Rolling with laughter ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

Post #145746 10th Oct 2012 8:58am
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47p2



Member Since: 05 Oct 2010
Location: Gone Beyond, Subaru
Posts: 8048

Scotland 

JOKER wrote:
Surprised you haven't posted pictures up of your oh so wonderful garage as you normally do ya glaikit looking botten � Yawn Rolling with laughter


Looks like this when I open the door and the heat escapes ya dobber Laughing Laughing

Post #145749 10th Oct 2012 9:09am
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JOKER



Member Since: 11 Sep 2008
Location: Sconnie Botland
Posts: 15876

Scotland 

That because you're not allowed to fart in the Hoose ya eejit Laughing Laughing ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

Post #145750 10th Oct 2012 9:13am
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47p2



Member Since: 05 Oct 2010
Location: Gone Beyond, Subaru
Posts: 8048

Scotland 

Posh people don't fart ya fud Whistle

Post #145755 10th Oct 2012 9:31am
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JOKER



Member Since: 11 Sep 2008
Location: Sconnie Botland
Posts: 15876

Scotland 

And how would you know that , you are just a Weegie that has moved into an area where all the old folk in Glasgow go to die and think they are snobs � Laughing ====================================

"Open Mike Night " sounded like a lot of fun until i found out i was going to an Autopsy

Post #145758 10th Oct 2012 9:35am
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