Hi guys. I have a 96 300tdi Disco. Its latest problem is really baffling me, and causing me loads of hassle!
Several weeks ago it was running fine. Then one day, driving along I noticed the rev counter started to work intermittently. Checked the wiring from the alternator (having had a broken connector on the wire that feeds the rev counter not so long ago) but that all seemed fine. Wasn't too bothered, so lived with it. Around this time I started a new job which didn't require me to drive to work, so I was only using the Disco occasionally at weekends. One morning I had to drive to work, and as luck would have it, the battery was flat as a pancake (even the clock was out). Called the AA who turned up and jump started it. The AA man had a fiddle and said the battery was knackered. He also said something was draining the battery quite considerably when the car wasn't running.
I bought a new battery, which didn't cure the problem - something was defiantly draining it at a considerable rate. This drain knackered the new battery. Put another new battery in (got a free replacement under warrantee) and same thing happened again, presumably due to the fact the batt was getting drained so quick then being left uncharged.
Anyway, a couple of weeks I eventually got round to fiddling with it with a more mechanically minded friend. We could not get to the bottom of the battery draining problem; we removed assorted fuses but nothing seemed to stop the drain. Out of desperation, in order to get the car running (have now quit the previous job and working freelance so need to get around) I fitted a battery isolator switch by the driver’s door, with the intention of isolating the power whenever I wasn't driving it to stop the drain. Also fitted a 110amp/hr marine battery which would hopefully cope with being drained a bit better.
This doesn't seem to have solved the problem though. The car struggles to start in the mornings. I now have to keep a jump pack in the boot and use this to get it going in the morning. Once started for the first time, it will start fine all day (turning the isolator off between trips of course!!).
Can anyone shed any light on the situation. I'm guessing I have two problems here:
1: Something is draining the battery. Based on the fact the rev counter started playing up at the same time as all of this started, I'm assuming it could well be the alternator playing up. Of course, it might just be a co-incidence. Do we think a new alternator will solve this problem?
2: Even with the battery isolated when not in use, the engine won't start first thing. Is this likely to be because my isolator switch or new cabling between the battery and the chassis aren’t man enough? (I have used the same stuff I have used on 300hp outboard engines, surly this will be man enough?!) I have to confess I havn’t yet checked the voltage of the batt first thing, and indeed at the end of the day after running around in it. I guess again this could point to the alternator not charging it enough.
Any help/advise/thoughts/suggestions would be gratefully received!!
Many thanks, Tim
PS. Nearly forgot to mention. Whilst fiddling with it with my mate, we discovered the brake lights aren't currently working. As far as I can recall they were working fine before all of this started (although can't be 100% sure as I don't check very often!). Have checked the bulbs and they're fine. Plugged a trailer lighting board in and the brake lights on that work fine....
Several weeks ago it was running fine. Then one day, driving along I noticed the rev counter started to work intermittently. Checked the wiring from the alternator (having had a broken connector on the wire that feeds the rev counter not so long ago) but that all seemed fine. Wasn't too bothered, so lived with it. Around this time I started a new job which didn't require me to drive to work, so I was only using the Disco occasionally at weekends. One morning I had to drive to work, and as luck would have it, the battery was flat as a pancake (even the clock was out). Called the AA who turned up and jump started it. The AA man had a fiddle and said the battery was knackered. He also said something was draining the battery quite considerably when the car wasn't running.
I bought a new battery, which didn't cure the problem - something was defiantly draining it at a considerable rate. This drain knackered the new battery. Put another new battery in (got a free replacement under warrantee) and same thing happened again, presumably due to the fact the batt was getting drained so quick then being left uncharged.
Anyway, a couple of weeks I eventually got round to fiddling with it with a more mechanically minded friend. We could not get to the bottom of the battery draining problem; we removed assorted fuses but nothing seemed to stop the drain. Out of desperation, in order to get the car running (have now quit the previous job and working freelance so need to get around) I fitted a battery isolator switch by the driver’s door, with the intention of isolating the power whenever I wasn't driving it to stop the drain. Also fitted a 110amp/hr marine battery which would hopefully cope with being drained a bit better.
This doesn't seem to have solved the problem though. The car struggles to start in the mornings. I now have to keep a jump pack in the boot and use this to get it going in the morning. Once started for the first time, it will start fine all day (turning the isolator off between trips of course!!).
Can anyone shed any light on the situation. I'm guessing I have two problems here:
1: Something is draining the battery. Based on the fact the rev counter started playing up at the same time as all of this started, I'm assuming it could well be the alternator playing up. Of course, it might just be a co-incidence. Do we think a new alternator will solve this problem?
2: Even with the battery isolated when not in use, the engine won't start first thing. Is this likely to be because my isolator switch or new cabling between the battery and the chassis aren’t man enough? (I have used the same stuff I have used on 300hp outboard engines, surly this will be man enough?!) I have to confess I havn’t yet checked the voltage of the batt first thing, and indeed at the end of the day after running around in it. I guess again this could point to the alternator not charging it enough.
Any help/advise/thoughts/suggestions would be gratefully received!!
Many thanks, Tim
PS. Nearly forgot to mention. Whilst fiddling with it with my mate, we discovered the brake lights aren't currently working. As far as I can recall they were working fine before all of this started (although can't be 100% sure as I don't check very often!). Have checked the bulbs and they're fine. Plugged a trailer lighting board in and the brake lights on that work fine....
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