FBH problem

[Mark2000cc]

Hi,i have fitted a fbh today and had to wait until now for the temperature to drop below 5c.
When i fitted it i tested it by pin 3 and a bit of wire method and it fired up and did its thing.
Just been out to the car and......zilch! the temperature is 3.5c outside and there is nothing happening with the fbh,not even the pump is clicking like before when i tested it.
Its almost like there is no power to any of it,or its not communicating with the temperature sensor if that makes sense.
Could someone advise on what the problem might be,it was working when i did the test:(:confused:

[Mark2000cc]

anyone ?:):confused:

[Greeners]

Did you prime the pump...?

[oldcarguy]

More than likely it is the temp sensor which is fitted to the power steering oil rail which runs across the front of the radiator, if it's the original Rover one, it has probably packed up. You need to source an upgraded LR one, which is more accurate.

[Mark2000cc]

yes greeners i used a syringe to push diesel all the way,until it came out of the pipe under the bonnet

[Mark2000cc]

More than likely it is the temp sensor which is fitted to the power steering oil rail which runs across the front of the radiator, if it's the original Rover one, it has probably packed up. You need to source an upgraded LR one, which is more accurate.would that show a innacurate temperature?
I have tested the outside temperature with other means and its spot on what it shows on the dash?

[Mark2000cc]

I know its definately cold enough though,and its reading cold enough (3.5c)on the dash so in theory it should fire up no?

[James.uk]

If it fires up when you earth it, but not at 5c or less, then something is wrong between the unit and the sensor... :o

Might be worth rigging up an on-off switch if all else fails.. :}
...

[David Lawrence]

If it fires up when you earth it, but not at 5c or less, then something is wrong between the unit and the sensor... :o

Might be worth rigging up an on-off switch if all else fails.. :}
...




Have you run the car for long in between testing and then rechecking now? Is it possible that the FBH has gone in to lock out mode in which case you will need to reset it by pulling fuse 8 in the engine compartment and waiting 10s before plugging it back.

The other possibility is F8 has blown. I had the experience when messing with mine too many times close together to have that fuse blow. It is a 15A fuse and the unit draws all of that when it first fires up, so too many repeat tests too close together can cause it to blow.

[Kev75]

Hi There,
Pull the plug off the temp sensor and check you have 12 volts on one of the wires when the engine is running, if you have 12 volts check the other wire for continuity to FBH.If any test fails check the wires from the temp sensor, mine had rubbed through on the top edge of the intercooler, take the bumper off and right hand headlight off much better access. Kev
PS engine must be running as the temp sensor gets its power from the alternator.If it passes both tests the temp sensor is us try bridging the plug wires if the FBH work now change the sensor or fit switch inplace of sensor,if you fit a switch on the sensor wires heater will only work with engine running.Kev

[oldcarguy]

would that show a innacurate temperature?
I have tested the outside temperature with other means and its spot on what it shows on the dash?

I think your getting confused with the outside temp sensor and the FBH temp sensor. Two totally different things. Both behind the front bumper.

[Mark2000cc]

I think your getting confused with the outside temp sensor and the FBH temp sensor. Two totally different things. Both behind the front bumper.

Ah right, I didn't know that, how would I fit a basic override switch then, is it a simple job? Has anyone got a link to one, and better still, would anyone be able to help me fit it, i don't mind travelling a bit :-)

[oldcarguy]

I got mine from Rimmers , part number JWL000020, it was listed as not in stock, but it only took a day for them to get it. Or you can try your local LR dealer.

[suffolk boy]

also worth checking the wiring to the sensor.a member had the same problem with one i fitted turned to be the wiring to the sensor had worn away

[Mark2000cc]

Ok thanks guys, when the bumper is off, which side is the sensor, and is it attached to the bumper? Thanks again :-)

[suffolk boy]

Ok thanks guys, when the bumper is off, which side is the sensor, and is it attached to the bumper? Thanks again :-)
it is the big round one on the drivers side.not the thin probe looking one that is for the ipk

[humptynumpty]

what is the colour of the cables to bridge or earth because it looks like there is a 6 pin plug and a 2 pin plug above but on the 6 pin plugit only has 2 cables on left side with bottom pin empty and i think only 1 or 2 on right