Discussion
I had signed off this forum last week when I sold my 400. It had given me a bit of flat battery trouble now and then but having has an electrician out to sort out the alarm last month he tested the battery and had 12.75 volts cold, and confirmed that it was charging properly. I assume that something is draining the battery when the car's sitting there.
However, the new owner's just texted me asking if I know why the battery's gone flat after only 2 days after he was out in it. The short answer is that I don't have a clue. I feel sorry for him as I genuinely thought the that car was perfectly OK. I seem to recall that other threads over the years indicate that this can be a bit of a problem, does anyone know the the problem is, as I'd like to offer the guy some advice.
However, the new owner's just texted me asking if I know why the battery's gone flat after only 2 days after he was out in it. The short answer is that I don't have a clue. I feel sorry for him as I genuinely thought the that car was perfectly OK. I seem to recall that other threads over the years indicate that this can be a bit of a problem, does anyone know the the problem is, as I'd like to offer the guy some advice.
Things I have had in 12 months of ownership:
1. Duff battery (might not have been obvious - mine was producing the right voltage and charging ok, but I noticed battery acid on the carpet next to the battery box, so took it for testing and the battery place's battery diagnostic tool said bad battery. Changed it for a new Exide Excel 705, car turned over so much faster on start-up)
2. 100 amp fuse has blown and the car has been running on battery - was the engine turning over slower on start-up in the last couple of days? Easy to test - see if you can find 12 volts at the back of the alternator with a multimeter (£8, Maplins) with the engine not running.
3. Immobiliser on its last legs, and it has drained the battery overnight (ask him if he noticed the indicators permanently on one side, ie not flashing, just on - that's what mine did when the immobiliser was dying).
4. Something else has been draining it
5. He left the lights on (no audible warning, unlike almost every other modern car)
New battery is about £85 fitted - suggest he takes it to a battery place and has it thoroughly tested and replaced if necessary. Batteries last about 5-6 years on average - how old is yours?
1. Duff battery (might not have been obvious - mine was producing the right voltage and charging ok, but I noticed battery acid on the carpet next to the battery box, so took it for testing and the battery place's battery diagnostic tool said bad battery. Changed it for a new Exide Excel 705, car turned over so much faster on start-up)
2. 100 amp fuse has blown and the car has been running on battery - was the engine turning over slower on start-up in the last couple of days? Easy to test - see if you can find 12 volts at the back of the alternator with a multimeter (£8, Maplins) with the engine not running.
3. Immobiliser on its last legs, and it has drained the battery overnight (ask him if he noticed the indicators permanently on one side, ie not flashing, just on - that's what mine did when the immobiliser was dying).
4. Something else has been draining it
5. He left the lights on (no audible warning, unlike almost every other modern car)
New battery is about £85 fitted - suggest he takes it to a battery place and has it thoroughly tested and replaced if necessary. Batteries last about 5-6 years on average - how old is yours?
Battery failure is first choice.
But if not, then the 100 amp fuse would give the symptoms you describe, assuming the car won't run for long after jump starting.
Ask him how far he drove and if he noticed anything odd (speedo mis-reading for example). You can generally run about 40-50 miles after the 100 amp fuse has blown. Car will then just stop running after going down on power. They just seem to let go when they feel like it.
I have had it happen twice, no logical reason either time.
Last time mine went was probably the day before a track day. I thought the car was slightly sluggish starting on the day of the track day, but had friends with me, so ignored it. Drove 20 miles to the track, and about 10 laps in I suddenly had a spin i wasn't expecting, and the battery was too flat to restart the car. I think the engine dying had locked up the rear axle as I changed down, causing the spin. Stuck a multimeter on the alternator side of the fuse - nowt. Changed the fuse, no further problems.
If he wants to find the fuse, it is usually strapped to the underside of the fore/aft chassis member where the rear arm of the lower driver's side wishbone meets the chassis. It will be in a black plastic fuse holder. It's the logical place for it IF you are building the car on a hoist. Not so logical if your car stops at the side of the road in a downpour.
But if not, then the 100 amp fuse would give the symptoms you describe, assuming the car won't run for long after jump starting.
Ask him how far he drove and if he noticed anything odd (speedo mis-reading for example). You can generally run about 40-50 miles after the 100 amp fuse has blown. Car will then just stop running after going down on power. They just seem to let go when they feel like it.
I have had it happen twice, no logical reason either time.
Last time mine went was probably the day before a track day. I thought the car was slightly sluggish starting on the day of the track day, but had friends with me, so ignored it. Drove 20 miles to the track, and about 10 laps in I suddenly had a spin i wasn't expecting, and the battery was too flat to restart the car. I think the engine dying had locked up the rear axle as I changed down, causing the spin. Stuck a multimeter on the alternator side of the fuse - nowt. Changed the fuse, no further problems.
If he wants to find the fuse, it is usually strapped to the underside of the fore/aft chassis member where the rear arm of the lower driver's side wishbone meets the chassis. It will be in a black plastic fuse holder. It's the logical place for it IF you are building the car on a hoist. Not so logical if your car stops at the side of the road in a downpour.
QBee said:
Robert Lees said:
Mine went flat because of the rear interior light. Put car in garage, not shut passenger door properly. Turned off permanently now!
I have had that happen too - God knows how it draws that much power, but it doesThis can cause the battery to go flat even with the interior light permanently switched off.
And I agree, it's amazing that such a small drain can cause a low or even flat battery in just a few days.
Hi All
I'm the new said owner of the TVR Chimaera 400, Rob I know where you live and I'm coming to get you!!!! (only joking)
Love the car and big smiles all round until this problem. Drove the car over the weekend, not that far but a few local trips to get the hang of her. Drove sat, car left overnight, started no problems sunday morning. Drove around sunday, say 40 miles in total, car sat outside friends house for 2-3 hours, again started no problems. Parked car in garage on sunday, went to start tuesday evening and car door wouldn't open, opened on third attempt. Could hear fuel pump priming but nothing else, lights seem to work but not sure how bright really. Anyway put the battery on fast charge and an hour later all was well. Left on normal charge overnight (like trickle charge I guess) and next morning still ok. Disconnected battery charger and then left for 24 hours, car didn't start again.
Does this sound like a flat battery or maybe this fuse I saw someone mention? As Rob said battery is only just 2 years old (March 2011). I want to drive to Torquay this weekend and can put the car on charge overnight to get me back but if it is something else will I end up stuck on the hard shoulder somewhere?
Any/all feedback much appreciated. Spoke to David Hendry in Malmesbury who supplied the original battery and they say might need a new one at £150 fitted!!! I believe the car has always been on a trickle charge when not in use (Rob?) so does this sound correct, as I said it is only 2 years 2 months old.
Many thanks in advance
Ian
I'm the new said owner of the TVR Chimaera 400, Rob I know where you live and I'm coming to get you!!!! (only joking)
Love the car and big smiles all round until this problem. Drove the car over the weekend, not that far but a few local trips to get the hang of her. Drove sat, car left overnight, started no problems sunday morning. Drove around sunday, say 40 miles in total, car sat outside friends house for 2-3 hours, again started no problems. Parked car in garage on sunday, went to start tuesday evening and car door wouldn't open, opened on third attempt. Could hear fuel pump priming but nothing else, lights seem to work but not sure how bright really. Anyway put the battery on fast charge and an hour later all was well. Left on normal charge overnight (like trickle charge I guess) and next morning still ok. Disconnected battery charger and then left for 24 hours, car didn't start again.
Does this sound like a flat battery or maybe this fuse I saw someone mention? As Rob said battery is only just 2 years old (March 2011). I want to drive to Torquay this weekend and can put the car on charge overnight to get me back but if it is something else will I end up stuck on the hard shoulder somewhere?
Any/all feedback much appreciated. Spoke to David Hendry in Malmesbury who supplied the original battery and they say might need a new one at £150 fitted!!! I believe the car has always been on a trickle charge when not in use (Rob?) so does this sound correct, as I said it is only 2 years 2 months old.
Many thanks in advance
Ian
You need to check if the car is charging the battery for certain.
If you put a volt meter across the battery before you start the car you should see something in the region of 12.5 - 13v. Then start the car and you should immediately see about 14v. If not then the battery is not being charged and it could be the 100A fuse or a duff alternator.
If it is charging then it is most likely the battery, or else a massive draw somewhere.
If you put a volt meter across the battery before you start the car you should see something in the region of 12.5 - 13v. Then start the car and you should immediately see about 14v. If not then the battery is not being charged and it could be the 100A fuse or a duff alternator.
If it is charging then it is most likely the battery, or else a massive draw somewhere.
As Bill's link says, jack the car up driver's side front using the normal jacking point under the corner of the outrigger and put an axle stand in. then slide on your back under the car from the front, so your head comes level with the back of the lower offside front wishbone. The fuse is attached near the chassis rail, inboard of the wishbone.
I stress, it's driver's side, basically straight down and a little back from the alternator.
I stress, it's driver's side, basically straight down and a little back from the alternator.
TorqueVR said:
I had signed off this forum last week when I sold my 400. It had given me a bit of flat battery trouble now and then but having has an electrician out to sort out the alarm last month he tested the battery and had 12.75 volts cold, and confirmed that it was charging properly. I assume that something is draining the battery when the car's sitting there.
However, the new owner's just texted me asking if I know why the battery's gone flat after only 2 days after he was out in it. The short answer is that I don't have a clue. I feel sorry for him as I genuinely thought the that car was perfectly OK. I seem to recall that other threads over the years indicate that this can be a bit of a problem, does anyone know the the problem is, as I'd like to offer the guy some advice.
Get him to charge the battery then disconnect small lead on the alternator, chances are the diode pack is shot causing a parasitic drain, mine cause a 3.4 amp drain and the battery wound be dead overnight.However, the new owner's just texted me asking if I know why the battery's gone flat after only 2 days after he was out in it. The short answer is that I don't have a clue. I feel sorry for him as I genuinely thought the that car was perfectly OK. I seem to recall that other threads over the years indicate that this can be a bit of a problem, does anyone know the the problem is, as I'd like to offer the guy some advice.
PS - Forgot to say that tested battery via voltmeter after being on charger all day. Cold reading was 12.75 then 14 when engine running. Turned engine off and left for 5-10 mins. Car wouldn't start again and when I tested with voltmeter again reading showing 11.5ish. Does this sound like battery?
Certainly sounds like it isn't holding a charge. Just changed mine. Well worth it. Local battery place did the work. Cost me £7 more than I would have paid online and having to do the job myself. They will have all the testers etc to confirm you are correct. And the hoist to make the working level easier.
FWIW, to get the battery out you remove the carpet, pull all the ECU and rats next away, undo the battery connections, undo the two retaining nuts and washers from under the car, and lift first and then slide the battery box and battery up and backwards, so as to release the bolts from the holes in the floor first.
The battery box is held in the car by a metal bar with two screw threads protruding downwards, that sits inside the battery box with the threads pointing downwards. As simple as that. It's fiddly and awkward, just to remind you it was designed by TVR.
Just thought ths might be useful when the nice battery man cannot fathom it
FWIW, to get the battery out you remove the carpet, pull all the ECU and rats next away, undo the battery connections, undo the two retaining nuts and washers from under the car, and lift first and then slide the battery box and battery up and backwards, so as to release the bolts from the holes in the floor first.
The battery box is held in the car by a metal bar with two screw threads protruding downwards, that sits inside the battery box with the threads pointing downwards. As simple as that. It's fiddly and awkward, just to remind you it was designed by TVR.
Just thought ths might be useful when the nice battery man cannot fathom it
Edited by QBee on Saturday 15th June 06:19
Bugger bugger bugger
Battery tested at Bathwick Tyres this morning. Battery is good!!! Car has started and driven alright this morning so makes me think I have an intermediate electrical fault......the worse kind.
One question for everyone, this 100A fuse, would this stop the car from running? Someone said that after 40-50 miles the car would stop. I have done that, not in one journey but certainly over the last two or so. I'm going to check it regardless as one less thing to worry about however I'm going to take it to Torquay tomorrow and wondered if I might break-down on route.
Thanks to everyone for feedback, has been most useful to a TVR novice. Expected problems along the way, having had classic cars in the past (Datsun ZX280, xjs 4.0 and BMW 635) but not this soon.
Battery tested at Bathwick Tyres this morning. Battery is good!!! Car has started and driven alright this morning so makes me think I have an intermediate electrical fault......the worse kind.
One question for everyone, this 100A fuse, would this stop the car from running? Someone said that after 40-50 miles the car would stop. I have done that, not in one journey but certainly over the last two or so. I'm going to check it regardless as one less thing to worry about however I'm going to take it to Torquay tomorrow and wondered if I might break-down on route.
Thanks to everyone for feedback, has been most useful to a TVR novice. Expected problems along the way, having had classic cars in the past (Datsun ZX280, xjs 4.0 and BMW 635) but not this soon.
Gassing Station | Chimaera | Top of Page | What's New | My Stuff