Jimny battery flat again?

Hi all

Since I bought my Jimny about 7 months ago, I've had the battery go too flat to start it 3 or 4 times. Once I left the sidelights on (for about 7 hours, and it was totally dead when I got back to it), but other than that, it just seems to go flat over time. I mainly use it for shortish journeys (2 x 4-5 miles per day, 3 - 5 days a week). A month or so ago it went flat, so I checked the electrolyte levels (which were very low), topped them up and conditioned it on a decent battery charger. The charger was happy that the battery was fine, so I put it back in the car, and it worked for a while. Recently though I noticed it getting a bit hesitant to start on cold mornings. so I took it for a decent long drive on Sunday - 2 x 10-15 miles. On the way home though, I did stop at a shop, so had to restart the engine for a final mile or so. I didn't think this would be a problem, after having done several big drives already on Sunday, but the car wouldn't start this morning. It cranks very slowly, but won't actually spring to life.

So, it seems I have a problem. The battery in the car is a 45AH Banner Starting Bull, doesn't look too old. And the alternator is putting out decent charge current, as the breakdown chap checked it when he jump started me. The car has an aftermarket stereo with a DVD player fitted, but I took it out, and all the wiring looks proper - i.e. proper multipin connectors, not cut and taped wiring or anything dodge. I can't turn the stereo off once it's turned on (no off button!) but it does seem to go fully off when the ignition is off or when the faceplate is removed. The car doesn't have an alarm, at least as far as I know.

So, do I need a new battery? Is it worth trying to recondition the old battery again? Should I check current leakage with everything turned off? (I've got a multimeter, but am not sure exactly what to check and where). Finally, if I do get a new battery, is there any point paying more money for an Exide battery with an extra 60 CCA (cold cranking amps)? There are several batteries that ECP / CP4L say would suit my Jimny - one by Lion, one by Bosch, and one by Exide. All are 45ah, but the Exide one is a bit more expensive and has 390 CCA against the Bosch battery's 330. Will this actually make a difference to cold starting? Or am I just using the Jimny too infrequently / not for long enough journeys, and I'm always going to have the battery going flat over time? I know various people on here keep their Jims on trickle chargers, but surely that shouldn't be necessary in a modern-ish car? My ancient sportscar has never had a trickle charge in its life, and it's never gone flat on me over the past 6 years, despite being left for weeks at a time with no usage. It does of course have a bigger battery to be fair, but it also has a much bigger engine to start with it...

Thanks for any advice.

Sandspider wrote: Hi all

Since I bought my Jimny about 7 months ago, I've had the battery go too flat to start it 3 or 4 times. Once I left the sidelights on (for about 7 hours, and it was totally dead when I got back to it), but other than that, it just seems to go flat over time. I mainly use it for shortish journeys (2 x 4-5 miles per day, 3 - 5 days a week). A month or so ago it went flat, so I checked the electrolyte levels (which were very low), topped them up and conditioned it on a decent battery charger. The charger was happy that the battery was fine, so I put it back in the car, and it worked for a while. Recently though I noticed it getting a bit hesitant to start on cold mornings. so I took it for a decent long drive on Sunday - 2 x 10-15 miles. On the way home though, I did stop at a shop, so had to restart the engine for a final mile or so. I didn't think this would be a problem, after having done several big drives already on Sunday, but the car wouldn't start this morning. It cranks very slowly, but won't actually spring to life.

So, it seems I have a problem. The battery in the car is a 45AH Banner Starting Bull, doesn't look too old. And the alternator is putting out decent charge current, as the breakdown chap checked it when he jump started me. The car has an aftermarket stereo with a DVD player fitted, but I took it out, and all the wiring looks proper - i.e. proper multipin connectors, not cut and taped wiring or anything dodge. I can't turn the stereo off once it's turned on (no off button!) but it does seem to go fully off when the ignition is off or when the faceplate is removed. The car doesn't have an alarm, at least as far as I know.

So, do I need a new battery? Is it worth trying to recondition the old battery again? Should I check current leakage with everything turned off? (I've got a multimeter, but am not sure exactly what to check and where). Finally, if I do get a new battery, is there any point paying more money for an Exide battery with an extra 60 CCA (cold cranking amps)? There are several batteries that ECP / CP4L say would suit my Jimny - one by Lion, one by Bosch, and one by Exide. All are 45ah, but the Exide one is a bit more expensive and has 390 CCA against the Bosch battery's 330. Will this actually make a difference to cold starting? Or am I just using the Jimny too infrequently / not for long enough journeys, and I'm always going to have the battery going flat over time? I know various people on here keep their Jims on trickle chargers, but surely that shouldn't be necessary in a modern-ish car? My ancient sportscar has never had a trickle charge in its life, and it's never gone flat on me over the past 6 years, despite being left for weeks at a time with no usage. It does of course have a bigger battery to be fair, but it also has a much bigger engine to start with it...

Thanks for any advice.

390 CCA versus 330 CCA makes no difference. Don't know if you have a winch. But a quality battery with high CCA is preferable. I think the Odyssey PC1200 fits right in the Jimny. But it is an expensive battery.

Thanks.

I don't have a winch - just want a battery that will last a bit better. The Odyssey one looks good, but bastardly expensive! Surely I don't need anything that hardcore for a standard Jimny that's used regularly? And would the extra 60CCA of the Exide battery not help on cold starts? (Not if the battery is fully flat, but if the battery is just low...?)

Cheers.

The extra capacity will help on cold starts, a higher quality battery will also hold its charge longer. You should use a multi-meter to check the current draw, some cheap stereos will run the battery down relatively quickly.

the Banner batteries are not good i work at a battery company and we find Banner stuff dose not last more than a a year before you start getting problems for the suzukis we fit Exide, we also have Varta which make Bosch batteries

I had a similar problem just before Xmas, I stuck a Bosch S4 battery on it and problem solved. I think my old unit had a cell which was not performing as it should