P38 electrical gremlins -please help

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g1les

New Member
Posts
6
Location
Sussex UK
Hello, I have a 1999 4.6 P38 Range Rover (Thor). I have owned it for a couple of months, but before that it has been owned by my parents for over 10 years. It has only done 46,000 miles and whilst it will not have been driven hard, it will not have been serviced every year. It could be a great car, but the reliability issues make it a big problem especially as my wife (and 3 you children) want to use it.

The reason my parents passed the vehicle to me was that it has become unreliable, with various electrical issues. Principally these were:
1. When driving the speedo and rev counter suddenly drop to nothing. This is an intermittent problem and they can stay down for a period or flash up and down. It may not happen on some journeys and then on others it happens all the time or may stay down for 10 minutes.
2. This is accompanied by warning “beeps” and messages for example windows/sunroof not set
3. Sometimes the car will not start(nothing happens). The battery is fine (see below) and usually after a few attempts it will suddenly start.
4. Probably separate, and not important to me but just in case related I mention that the clock loses time.

I am not very good with cars and do not have the confidence to do much work myself, but I am quite good at problem solving (sometimes?!) and I have trawled the forum and found it very useful and informative and because of this I have undertaken the following works:

1. I got a local specialist in RR electrical to come and have a look. He checked all earths. Sniffed the under bonnet fuse box, took out the becm and cleaned it with a toothbrush and wd40 (since then I think I have seen that this is frowned upon). He could not find anything specific. The problems continued and his advice was to replace the under bonnet fuse box and if that did not fix it the becm.
2. I took the car to a local Land Rover independent garage. They said there was air conditioning fluid in the under bonnet fuse box which they cleaned out. At the same time I got them to fit the recommended aphaline battery and to replace the pollen filters. Again the problems persisted.
3. I got a local car electrician to look at the car, he saw the faults happening and cleaned a few earths. He said he found a few pinched wires, but the problems remained. On one day the problems were very severe with a lot of heat in the under bonnet fuse box and relays clicking with many warning beeps and warning lights with the car not starting. I got him to replace the under bonnet fuse box (with new fuses and the old relays put back in). I also asked him to perform the electrical tests sticky suggests in this forum which he says were all fine (but I am not convinced and I am afraid that I have lost faith in his ability to fix the car after 4 visits and him having it for 3 weeks).

So this is where it is now, the same problems identified at the very start still occur intermittently. I may have wasted much time and money, but I still do not want to give up on the car, she could be great!

As I have said above I am not very good mechanically and I have spent a good deal of time on the forum and could not find the same symptoms elsewhere (I hope I have not missed it!). I am downloading the RAVE CD as i type

Please help?! Many thanks in advance

Giles
 
Is the carpet wet in the drivers foot well? If it is there could be a corrosion, condensation problem with the BECM. If the BECM needs attention you need to contact rick the pick on here, he's the expert and repairs them for other garages.
However, corroded connections, & bad earths are the most likely problem if the fuse box has been replaced. Are you sure the garage actually replaced it?
Never use WD40 to clean contacts.
 
(1) Check alternator output voltage under full load if faulty this would explain some of the electrical symptoms that you describe



(2) Recheck under bonnet fuse box, remove the box to check properly and as suggested are you sure it was replaced ?



(3) BECM replace or repair


And maybe consider investing in diagnostics kit for the future.
Good luck and let us know how you get on
 
Is the carpet wet in the drivers foot well? If it is there could be a corrosion, condensation problem with the BECM. If the BECM needs attention you need to contact rick the pick on here, he's the expert and repairs them for other garages.
However, corroded connections, & bad earths are the most likely problem if the fuse box has been replaced. Are you sure the garage actually replaced it?
Never use WD40 to clean contacts.

Thank you fior your message. In answer to your question fusebox was definitely replaced with a new one -I was watching! The carpet does not seem to have got wet.
I will check the connections and earths and invest in a multimeter?!
 
(1) Check alternator output voltage under full load if faulty this would explain some of the electrical symptoms that you describe



(2) Recheck under bonnet fuse box, remove the box to check properly and as suggested are you sure it was replaced ?



(3) BECM replace or repair


And maybe consider investing in diagnostics kit for the future.
Good luck and let us know how you get on

Thank you. I will start with the wiring/earthing tests and the alternator and then take it from there. Would a diagnostics kit tell me where the problem was -or just what I know already -that there is a problem!

It is a new fusebox

many thanks
Giles
 
Thank you. I will start with the wiring/earthing tests and the alternator and then take it from there. Would a diagnostics kit tell me where the problem was -or just what I know already -that there is a problem!

It is a new fusebox

many thanks
Giles
Are you sure it's a new fuse box not just a different one, ie secondhand?
 
Hi, a few suggestions.
I would start with a voltage check on the battery leads, not the battery terminals. It is possible that dirty battery connections could be giving low volts even though the battery is new. For that matter the new battery could be faulty.

Was the new fuse box the correct one, they are different for model and year though almost identical to look at.

When the engine won't start does it turn over but not start or does nothing happen at all when you turn the key and does any message show at the time?

Don't give up and don't keep paying specialists, there is a goldmine of expertise right here on this forum.
 
Hi, a few suggestions.
I would start with a voltage check on the battery leads, not the battery terminals. It is possible that dirty battery connections could be giving low volts even though the battery is new. For that matter the new battery could be faulty.

Was the new fuse box the correct one, they are different for model and year though almost identical to look at.

When the engine won't start does it turn over but not start or does nothing happen at all when you turn the key and does any message show at the time?

Don't give up and don't keep paying specialists, there is a goldmine of expertise right here on this forum.

Many thanks. I will do the tests you suggest. I think it is the right one as I gave my Registration to main dealer and they provided.

When it will not start (which is very rare) noyhing happens at all. and no messages.
 
Many thanks. I will do the tests you suggest. I think it is the right one as I gave my Registration to main dealer and they provided.

When it will not start (which is very rare) noyhing happens at all. and no messages.
When it won't start does it crank?
Might be worth swapping the ignition and starter relays, you can interchange relays of the same colour.
 
could be faulty starter motor/bad connection. If clock is losing time time have you checked battery? Could just be a faulty clock!

Windows not set is eassy to fix. Have a quick search!
 
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