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Discussion Starter #1
Hi,

Amongst my Rover's (never ending!) list of "things to do" is to find an electrical gremlin. Occasionally I find that the battery is completely drained and the Rover is in need of a jump start. Once she's fired up everything will is fine for quite some time (say a month or two) and then it happens again. Nothing has been accidentally left on and everything appears to be off when the car is left.

The battery condition and charging has been checked and is good. This is backed up by the fact that she runs well even with regular and short "round town" trips and never shows signs of struggling to start.

It would appear that something is occasionally not switching off after the ignition key is out (e.g. EAS delay relay etc) or something is switching on of its own accord.

On 3 occasions I have gone into the garage to find that all the direction indicators are on - steady, not flashing. They were not on when the car was locked, but have switched on sometime after.

I know that the indicators are linked to the alarm, inertia switch, central locking etc, but there are no dash messages apparent that would imply the alarm or switch has triggered or anything else. Unlocking and locking the doors again clears the problem.

I'm not expecting any miracle answers 'cos I know it's going to be very hard to find a very intermittent electrical fault. I was just wondering if someone has come across these symptoms before and whether there might be a cure.

Cheers
Tom
 

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Hi,
I have very similar problems, but have had the added joy of the BeCM and alarm module sometimes losing their security sync in the process. I am led to believe that the original alarm module fitted to the P38 is susceptible to RF interference (I see it on mine most frequently when other people unlock or lock their cars nearby with their remote keyfob). Apparently the BeCM can be 'awakened' in a random way, setting some various parts of the electrics off, and draining the battery. Sometimes it may not be a visible thing. There is a solution whereby a later version of the module can be fitted which isn't responsive to random RFI - this is what I'm doing this week!
 

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Hi Tom,

the battery draining was a common problem on earlier model RRs. The newer models like ours have had the remote radio system sensitivity reduced and filtered to stop random Becm awakenings. But, if there is a nearby radio interference source on a similar frequency then it is still going to happen. Have a look around for any transmitters close by. Garage Door system, Ham Radio guy next door, stuff like that.
I once parked in the main street of a country town and my system refused to work completely I had to use the key, how menial. As soon as I moved the rangie everything returned to normal.

Why the indicators are all on, I have no idea. Does anyone else know why that happens??

I am not sure if my experiences are similar but I have had the battery die twice on me and I am unable to pinpoint any reason. The second time was with an Optima Yellow Top that was only 1 year old and the alternator was checked to be fine. The battery had failed and Optima Australia refunded the replacement cost, thanks Optima :)

Cheers
Mick
 

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Your problem will be caused by excessive voltage drop in your battery cables between the alternator and the battery.

A weak battery will actually cause the BECM to do this.

Part 1. Charge the battery with a good 3 stage battery charger for 24 hours minimum
Part 2. Fix the faulty battery cable.

I've rewritten the electrical sticky and it will be back in a couple of days after a few members proof read it. All the troubleshooting info you need is there.

In the meantime charge your battery with a PROPER 3 stage (or 4 stage or better 8 amp or better) charger.

Greg
 

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Hi all,

great tip Greg, when I return from my hiatus at work, I shall break out the meter and check out my ground cable.

Could it be this simple Tom? whats the bets?? hehehe

Cheers
Mick
 

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Bad cables cause weak battery charge. When the battery gets low enough it causes the lights to come on by themselves like you say. It only happens in certain circumstances, eg if the battery gets low from sitting for months or years it doesn't happen, I don't think. It has something to do with starting the car or switching it off.

You may also find your car is going into police mode when you drive it. The BECM is programmed with a police lighting option which flashes one headlight then the other and also does other tricky stuff with all the other lights. Maybe they fixed that particular issue in the later models but my 94 did it to me a few times and it took ages to work out why. People would pull off the road thinking I was a police officer which is funny as in Australia we've never used RR's let alone unmarked ones!

Your problem won't be the alarm module, other than it may be waking up the BECM due to hearing too many radio signals. It is within the BECM. And I would bet it is battery voltage and excess voltage drop on your charging cables.

Hit your battery with a good 3 stage or better charger. Then fix the cables, that is all you will have to do. I am a little suprised that the later bosch models still have this problem but there you go.
 

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Discussion Starter #8
Hi guys,

Thanks for the input.

As for RF interference... well we have a garage door opener (which there seems to be no correlation with), but the neightbours have them as well. Unless there are just some very occasional and random occurances triggering it.... I guess it's something I have to live with.

I look forward to the electrical sticky Greg. If I understand you correctly, you're saying that the lights come on randomly when the battery's almost drained below it;s correct cvoltage, right? However, that's not what I am seeing. The few times I have "caught" Rover with the indicators on, it has been a few minutes after I have left it. If I unlock the car the indicators go out and starting up the engine is a breeze - no evidence of it struggling to crank or anything, no other lights doing funny things. I think the occasions the battery has been completely drained have been when the indicators are on and we have been away for a while and not caught it in time. I will check the cables as you suggest though.

BTW, the police mode is quite the party trick! Those boys in Solihull had a sense of humour `)

Tom
 

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It seems to happen to me when people unlock or lock their cars nearby. For example, my gf's dad noticed that my hazards were on solid on Friday night, but briefly went off when he locked his van (only to come back on again after a few seconds and drain the battery over the following few hours). I took the RR into a local specialist last week and they suggested the same problem with the alarm module and that they could replace it for £240 fitted.
 

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tbrown944 said:
If I understand you correctly, you're saying that the lights come on randomly when the battery's almost drained below it;s correct cvoltage, right? However, that's not what I am seeing. The few times I have "caught" Rover with the indicators on, it has been a few minutes after I have left it. If I unlock the car the indicators go out and starting up the engine is a breeze - no evidence of it struggling to crank or anything, no other lights doing funny things. I think the occasions the battery has been completely drained have been when the indicators are on and we have been away for a while and not caught it in time. I will check the cables as you suggest though.Tom
The battery will still have heaps of capacity to start the car. If it didn't, diagnostics would be EASY and Lucas Electrical Price of Darkness would have no fun with us.

Belive me I've been through it and so have many others.

You can check if the alarm module is the problem pretty easily. It won't matter if it gets woken a few times a day, you are looking to see if it is awake all the time.

Also, there is no need to replace the module, disconnecting the alarm antenna and just using the receiver close to the car will do just as well.

Read this: viewtopic.php?f=3&t=39058

Then post answers to all these questions in THIS thread.

Worksheet

This is a cut down version of the tests, please read the detail on how to complete each test.

1. Engine off, all accessories on for 30 seconds, then off. What voltage ______
2. Voltage across battery at idle (no electrical load) ____________
3. Voltage across battery at 2000rpm (no electrical load) ________
4. Voltage across battery at 2000rpm (everything electrical switched on) _________
5. Voltage at ALTERNATOR at 2000rpm (everything switched on)___________________
6. Voltage drop between alternator body and battery negative (YES negative). Measure at max electrical load and 2000rpm ______________ (millivolts please)
7. Voltage drop between alternator positive and battery positive. 2000rpm, max electrical load _____________
8. Check Voltage drop from Battery Negative terminal to 1st groundpoint on vehicle______________
9. Check voltage drop from 1st ground point to block__________
10. Check voltage drop from Alternator Housing to block__________
11. Voltage from alternator positive to alternator housing

What are your symptoms
What have you done to fix it so far
 

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I'd be leaning towards a bad battery purely in what you mentioned in the last reply " a few hours later and its flat" do you know the history of your battery.

If it comming up to three years, used alot for town driving I'd get it load tested.
Your charge rate on idle should be around 14.2 volts and should be your first test.
 

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viperover said:
I'd be leaning towards a bad battery purely in what you mentioned in the last reply " a few hours later and its flat" do you know the history of your battery.
Until your battery has had 24 hours on an 8 amp 3 stage (or more stage) charger and your battery has 14.2 volts or better still 14.4 volts across it while the engine is running with all accessories on at 2000rpm, I wouldn't go replacing the battery.

You'll just kill another one in short order. I was replacing them every year for a few years due to police mode, indicator problems etc until I decided to get to the bottom of it. I even had the alternator rebuilt but it was just the cables. The old batteries were stil usable after a decent charge.
 

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3 years battery life on average is considered good on the Range Rovers.
Also once a battery is calified there is no going back, battery maintainer chargers are just that, they cannot repair a damaged battery.
No battery charger is called a battery repair charger, what they do is manitain a state of charge called a float statecharge of around 13.2 volts vs a charger of somertimes 15 volts.

A good alternator is critical to the life of the battery and better than the best chargers out there as most over charge, though battery maintainers of the digital type are decent in keeping batteries in their charged state if the vehicle is not being used for long periods.

If all cables are in order then I'd start looking at other cabling issues like loose conections, bad earths etc, here soldering is king and rarely do cables need to be replaced.

On a few I've done some serious soldering on major connections and cables with very positive result.

GEMs engine should have a new cable dirtect from alt to battery which also doubles up the cranking starter cable by adding this very short cable if nice and thickish, electrics are simple but its the electroincs that cause confusion, all good fun I say..
 

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Hi VIP I can agree with many of the things you have said. 3 years may be average for a RR battery but it is unnecessary to kill a battery every 3 years. Any basic lead acid battery of a suitable size and half decent quality can last double that in a properly maintained RR. However, they probably do only last 3 years on average because they are not properly maintained.

For a RR which does lots of short trips, it is worth giving it 24 hours on a good charger every few months or at least once or twice around the middle of winter (where you would use lights etc the most) can make a huge difference.

Once a battery has been flatted once, it is never the same again and every time thereafter is worse. However it will probably still be sufficient if brought right back up to its full, but now lesser, best. Also if they are operated at partial charge, their life is greatly shortened.

Some of the battery repair chargers can work. They roast the battery with a relatively very high charge voltage and it can make a battery which people were going to throw out work quite well again.

Solding is not necessarily a good idea for battery cables in a car. Solder takes flexible cable and makes it solid which can make it prone to damage from vibration or movement. It also does not provide the same electrical connection as a quality mechanical crimp. The right mechanical crimp will give less voltage drop. You can solder as well (which will help further) but make sure you properly support the cable to protect it from being bent as it will fracture near where it has been soldered.

Absolutely a great idea to upgrade the battery cables direct to alternator. I'll be doing mine in zero gauge shortly.

Greg
 

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Yeah batteries are like engine oil, "which is best" and so on, its such a diverse subject that it gets to point that defies logic..

I placed a 3 year old battery on my snazzy digital processor controlled battery charger come what ever you wanna call it on charger over night, next morning I could have made a cuppa tea if it wasnt for the battery acid, mind you it was a Dixon battery which I rate as a zero on my liked battery list along with Willard, Sabat and some other funny fong kong junk.

We can get American batteries here and mind boggling prices for some odd reason so I supply and install the 105 amp Probe batteries from Brazil, apparently they also supply Voyager and Deltec with the exact same battery, just different stickers I guess.

Alt cable to battery should have been done long ago, it was an official LR update and a cable kit was supplied
 

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Sorry to sound foolish and hijack the thread a little, but would the following symptoms apply to a bad battery/charging circuit:

1 hour/45 mile journey, parked, no problem. After around 1 hour it was reported to me that the hazards were on solid, but switched off briefly when a nearby keyfob was pressed. Around 3 hours later I returned to the car to find that the battery was almost completely dead (just enough juice for central locking, not enough for engine turn-over). Morning after, the the car was jump-started, followed by a 1 hour drive to recharge. There have been no further battery problems since (Saturday).

??
 

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jimbohotpants said:
Sorry to sound foolish and hijack the thread a little, but would the following symptoms apply to a bad battery/charging circuit:

1 hour/45 mile journey, parked, no problem. After around 1 hour it was reported to me that the hazards were on solid, but switched off briefly when a nearby keyfob was pressed. Around 3 hours later I returned to the car to find that the battery was almost completely dead (just enough juice for central locking, not enough for engine turn-over). Morning after, the the car was jump-started, followed by a 1 hour drive to recharge. There have been no further battery problems since (Saturday).

??
The answer is yes. The tests take 5 minutes and you should do them. I promise you, a 1 hour drive won't properly charge your dead flat battery.
 

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Discussion Starter #18
Hi guys,

No problem hijacking the thread jimbo, all info is good and I am tending towards the alarm idea myself.

I am not convinced about the electrical issues. An autoshop has already checked out the car and reported that the battery and charging are in perfect order. The ONLY problem I have experienced is with the indicators, nothing else suspicious. The main thing is that rareness of it. If there were battery and/or charging issues I would expect the problems to be more regular. As it is, we go months with no problems then something happens and the battery goes flat. Get it going again and it's fine for another few months when it either goes flat again or I catch it with the indicators on etc..

I know you're hot on the electrical subject Greg and I am not dissing your ideas. I haven't checked the voltages yet (had family round and am working on some EAS issues which are more important at the moment), but i will do, I promise!!

What I HAVE done is disconnect the alarm antenna. Now the key fob will only work up to about 6 feet away. We'll see what happens. I have no direct evidence of another keyfob causing an issue like jimbo, but we'll see what happens.
 

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ghind said:
The answer is yes. The tests take 5 minutes and you should do them.
I will do the tests as soon as I can and report back :)

ghind said:
I promise you, a 1 hour drive won't properly charge your dead flat battery.
I think you missed:

jimbohotpants said:
Morning after, the the car was jump-started, followed by a 1 hour drive to recharge. There have been no further battery problems since (Saturday).
Evidently the battery WAS charged after an hour drive, since there have been no further problems.
 

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ghind said:
I promise you, a 1 hour drive won't properly charge your dead flat battery.
I think you missed:
jimbohotpants said:
Morning after, the the car was jump-started, followed by a 1 hour drive to recharge. There have been no further battery problems since (Saturday).
Evidently the battery WAS charged after an hour drive, since there have been no further problems.[/quote]
It may be charged enough to start the car, but it won't properly recharge that way. Battery capacity and life is decreased substantially by flattening them. The best thing you can do now is get a high quality battery charger (3 stage or better, 8 amp or better) and charge the battery for 24 hours.

p38's are picky about battery charge, run the tests and charge your battery.
 
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