P38 fuse box replacement

[Rextheute]

As part of my preventative maintenance on my p38 - esp as the fuel pump relay died and then on a very hot day the A/C was blowing at 48 deg ......... I checked the relays .
Fuse box was extremely hot and smelled of 'warm electricity '

So I rang the trusty Land Rover dealer and purchased a new fuse box , funnily enough they keep them on the shelf !
AMR6405 - manufactured late in 2015 - so there must be a demand ( can't imagine why )
Refitting in approx an hour , purchased 4 new relays for fuel pump and a/c fans .

All back together and yay the RR started !

Total cost was $350.00 for the fuse box and 4 relays , it not difficult to do and gives me confidence that I'm sort of on top of a couple of electrical gremlins that seem to affect these beasts 👻

[Rextheute]

As seen , the fuel pump relay location is burnt as is the a/c mount .

I looked at Ron's repair guide ,but I'm not that gifted ....

[Rextheute]

All out , these were the replaced relays - spare set .

[p38arover]

As seen , the fuel pump relay location is burnt as is the a/c mount .

I looked at Ron's repair guide ,but I'm not that gifted ....

I also eventually bought a new fusebox for mine.

If I recall correctly, there are different fuseboxes depending on year.

[Rextheute]

Good point regarding variations .
Mine is a 1995 4.6 hse , I think there is a super session chain which ends at this version - the Bosch ones are defo different .

[Keithy P38]

Good work mate! It's a simple job once you've done it hey!

[PeterH]

Good work!
Just out of interest, what is involved in replacing the fuse box?
I imagined it to be a complicated job with a billion wires, but Keithys comment has me questioning how hard it really is.
It's one of those jobs I may have to tackle one day.

[Rextheute]

Well , it's the hardest job ever ........... Nah only joking !

The main points are ;
Open drivers window , take key out of ignition

disconnect battery , negative terminal first , 13mm spanner

Swap out relays - take a picture if liable to get distracted .... I replaced the fuel pump and A/C relays with new ones ( as they were the burnt ones )

Undo the three retaining bolts 8mm socket

Carefully disconnect the plugs on base - all colour coded so simple to match up

Undo the earth straps for becms , 10mm socket

It's actually easier than other tasks I've undertaken on a p38 . Just go slow and careful.

Reconnect the battery - positive terminal first .

Then restart the car , I then reset the Windows ( poorly mind you ) and resynced the key fob - this is important as you can't lock it with the fob unless paired with vehicle .
Just make sure windows up , all doors and bonnet shut , use fob to lock and then lock drivers door with key , then unlock with fob .

Should be good then......

MLR at port Melbourne are very helpful - and keep the part in stock .

Give it a go !

[p38arover]

Good work!
Just out of interest, what is involved in replacing the fuse box?

Very, very simple. All the wires are on plugs which cannot be put back into the incorrect spots as they are keyed.

There are a couple of pics of the underside here: Fuse Box Repairs (http://www.rangerovers.net/repairdetails/electrical/fusebox.html#dismant)

[BritishCarComponents]

(if you havent already) extend the overflow pipe on the expansion tank so that it doesn't vent/dump near your new fuse box.

Replace pollen filters and plenum foam (buy wherever you want, but we sell them to AULRO friends everyday at trade prices) and clean everything in those areas as best you can... even try to vacuum right down into the intakes.

This should give everything else in the HEVAC System its best chance with easily blowing and distributing incoming air.

These things will not fix all the other possible problems, but they are a big part of the cause boards corroding/cracking and blend/blower motors being overworked.

:-) Dave

[p38arover]

Replace pollen filters and plenum foam (buy wherever you want, but we sell them to AULRO friends everyday at trade prices) and clean everything in those areas as best you can... even try to vacuum right down into the intakes.

This should give everything else in the HEVAC System its best chance with easily blowing and distributing incoming air.

These things will not fix all the other possible problems, but they are a big part of the cause boards corroding/cracking and blend/blower motors being overworked.

:-) Dave

I'm not convinced that blocked pollen filters cause the problem with RL7. Note, the problem is only with RL7, not RL6.

An electric fan running with a blocked intake filter draws less current, not more.

See Fundamentals of HVACR: Understanding Centrifugal Fan Motor Performance (http://hvacrfundamentals.blogspot.com.au/2009/08/understanding-centrifugal-fan-motor.html)

I must make up a test rig and put it on a P38A then take some current measurements with a new pollen filter and a blocked pollen filter.

[BritishCarComponents]

I'm not convinced that blocked pollen filters cause the problem with RL7. Note, the problem is only with RL7, not RL6.

An electric fan running with a blocked intake filter draws less current, not more.

See Fundamentals of HVACR: Understanding Centrifugal Fan Motor Performance (http://hvacrfundamentals.blogspot.com.au/2009/08/understanding-centrifugal-fan-motor.html)

I must make up a test rig and put it on a P38A then take some current measurements with a new pollen filter and a blocked pollen filter.

Hi Ron,

I don't think its only about that techo measures and current draw...

If the flow is restricted and the system needs to attempt to meet a lower or higher temp it is going to "Hunt" for a solution. Generally over using relays, flaps, blend and blower motors more than required to meet the target set by the user (or worse, two users with varying temp needs).

Surely... clear flow and no crap in the vents will do nothing more than assist?
At worst, you will reduce the unwanted air born particles (like pollen) coming into and through the system to the cabin.
At best, less "hunting" and longer component life.

Don't care if I am technically wrong, it just makes sense to me to keep it all clean and fresh in the inward bound air pathways... it can't do any harm either. Can it?

Hoo-Roo,

:-) Dave

[flathead steve]

Always seems to be the same corner of the fuse box all sorts of explanations but the end of the day put in a new one fixs a lot of problems split the boards have a look any damage and the car goes crazy huge influence on EAS HVAC and god knows what else pretty much everything