Electrical & Lights Battery Drain

Discussion in '7th Generation (2003-2008) [Acura TSX]' started by Heckler, Tuesday 3rd Nov, 2015.

  1. Heckler Top Contributor ★ ★ ★ ★ ☆

    Yesterday I went out to start the car which had been stood since Friday afternoon after a 25m trip and two 5m trips... and she turned over but wouldn't start... As I tried a few times it became obvious the battery was a little drained.

    I hadn't left anything on, no lights or anything plugged into 12v sockets (which are inactive if ignition is off as I double checked)... Got a jump and it started immediately, took it out for a 30 mine 15m drive to put some juice back in and then did a couple of errands. Car started first time 3 times after that with only short 2-3 min trips inbetween. Then I did the 25m drive back home in the evening.

    This morning I got the battery checked out and it's working perfectly... Not a thing wrong with it according to the gizmo/machine they stuck on it. But they only tested it whilst it was switched off... So I still want to test it whilst running to see if the alternator is charging it properly

    Did a couple more short trips of around 6m and started first time each time again.

    I'm a little stumped... this is the second time it's happened but the first was due to me leaving sidelights on. I stuck my charger on it for an hour and it's been fine for the last couple of months.

    Are there things I should be checking that may be a drain?

    Boot lights are switched off as are interior lights (well, they are now just in case) so only the puddle lights come on when you open the door... I rarely have the stereo on, no AC in this weather temp is set on average to 20-22 depending if it's the start of a journey or the car is fully warmed up. Occasionally use the heated drivers seat (have yet to test the passenger one actually).. but not actually used heated seats for about a week.

    What kind of power drain does the clock, headunit and so forth have... It was only about 66hrs from parking it up Friday afternoon to trying to start it again Monday lunchtime. I don't do a lot of mileage so the car is often left for 2 or 3 days at a time without incident.

    Tomorrow I'll turn the car around and run the extension out and put the charger on it for a few hrs... make sure it's fully charged up... But with winter upon us, I don't want to be left stranded unexpectedly and be waiting around for the breakdown cover to arrive... especially as I could be carrying my elderly folks as my dad is disabled and rather frail.
     
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  2. SpeedyGee Administrator Staff Team

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  3. Heckler Top Contributor ★ ★ ★ ★ ☆

    Mine is PFL so no HFT to deal with.
     
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  4. SpeedyGee Administrator Staff Team

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    Oh OK .. in that case how old is the battery ?

    And have you tested that it is indeed being charged ?
     
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  5. jimjams Expert Advisor ★ ★ ★ ★ ★

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    There are several reasons for this, and the best sequence for checking it is as follows

    1. the battery itself
    Even a 1-year-old battery can start to cause problems. The only truly reliable test is to measure the acid with a hydrometer, but modern "maintenance-free" car-batteries make this very difficult. The alternative is to use a proper load-tester, but the person using the load-tester has to know what they are doing, because the applied load depends on the Ah rating of the battery. If you leave it on a trickle-charger for a long period of time (usually over-night) that can help a lot

    2. the alternator/charging circuit
    IIRC on this car the way to check this is with engine running and the headlights on, and IIRC the voltage across the battery should be about 13.8 volts.

    3. parasitic drain
    if you are certain that the battery and the charging circuit are ok, then there have been incidents associated with a parasitic drain on something on fuse 7 (this is a separate issue from the known HFT issue). The best way to check this is a bit convoluted to explain, but basically you need to check the current drain from the car-battery with the car locked. To do this you will need to remove the negative chassis connection from the battery, and extend two leads outside of the car, one lead from battery negative, the other from the chassis connection lead. Before measuring the parasitic drain, you initially join the leads together, then with the bonnet shut, you lock the car (the reason for initially joining the leads is because there is a surge of several tens of amps, and then there is another lower surge when you lock the car). Now you place an ammeter (digital, not analog) across the point where the leads are joined, then disconnect the join with the ammeter bridging across. The measurement on the ammeter should be about 10 mA. But, even if the measurement is 10mA, there is a known issue with something on fuse 7 which causes a sporadic rise to about 100mA, and you need to keep looking at the ammeter to see if this occurs.
     
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  6. Heckler Top Contributor ★ ★ ★ ★ ☆

    Battery is a uniroyal with a 3yr warranty... but came with the car when I bought it. So no idea how old it is. It has been tested using a digital device, and the guy testing it did check something on the battery and then looked up what reading it should give on the device. I think this was something to do with the ah but didn't ask further questions about it.



    See my comment above regarding point 1.

    2: This is something I still need to get checked, the test they did yesterday had to be done with the engine off... and was just a battery test... I still need to make sure that the battery is being charged properly. Got some errands to run this morning, and when I get back... if it's stopped raining... I'll put the trickle charger on it for the day.

    3: Blimey... that is convoluted.... Will look into that if the other steps don't resolve.
     
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  7. jimjams Expert Advisor ★ ★ ★ ★ ★

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    ^ I reckon it's the battery
    sounds like he used a standard load-tester then looked at a table to interpret the results, which often gives a "false negative" i.e. failing state is ruled out incorrectly
     
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  8. jimjams Expert Advisor ★ ★ ★ ★ ★

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    one other thing that I just thought of, there is usually a date somewhere on the battery, from which you can work out how old it is
     
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  9. tonygw Valued Contributor ★ ★ ★ ☆ ☆

    This darker cooler weather puts a lot more strain on the battery due to cold cranking of the engine in the mornings, lights, heaters, demisters, heated seats etc combined with short trips can all have a detrimental effect. If the battery is weak you may experience starting issues such as this.

    Or if you have two young kids who leave the interior lights on, then that's is another drain on the battery, well that's what I get anyway... lol

    I actually invested in one of these portable jump starters from maplin. The battery it was fitted with was lower than the lowest quality I could imagine, so I swapped it for a decent branded battery and now the jump starter works great. Used it a few times and it comes in very useful when a flat car battery threatens to ruin your day. If I go on a long journey I often sling it in the boot just in case.
     
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  10. Heckler Top Contributor ★ ★ ★ ★ ☆

    I bought one of those battery packs a few years ago too... But I think I killed it as it no longer works... although if you plug in the charger, the lamp and air compressor do... But it no longer retains a charge. This was actually the second one I bought as I the first one was cheaper and only a jump pack and I killed that one too.

    Not sure if I still have it laying around here, if I do and it can be pulled apart I suppose i could look at changing the battery inside...

    I'm normally pretty careful about leaving things on... no heated screens, seats or heaters are switched on until the engine is running... I won't even turn the lights or stereo on until it's started... I've been doing that ever since I learned to drive. It's one of those little things my dad taught me because of the risk of battery drain, especially in colder weather.
     
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  11. tonygw Valued Contributor ★ ★ ★ ☆ ☆

    its good practice but even with the engine running all those systems are pulling current from the charging circuit so the battery will recover from its massive drain to crank the engine much slower. So short journeys with all those systems on means a much slower charging battery. Hence a short journey will not fully recharge the battery and eventually a weak battery may just give up.
    I tend to run the engine for 10 mins before switching the heavy loads on. Although sometimes its not possible if you need to demist to be able to see where you are going etc!

    The jump starters are good but unless you pay over £100 for them the batteries they use are really terrible quality and only last a couple of jump starts. Hence I bought a Yuasa battery to replace the junk they fit. Once it has a decent battery its quite a good bit of kit for light domestic use.
     
    Last edited: Wednesday 4th Nov, 2015
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  12. Heckler Top Contributor ★ ★ ★ ★ ☆

    Well I left it for 3 days on the drive (last used it Tuesday morning)... which is what happened last weekend... and it started fine this morning. Did several short trips of 1-2 miles and parked up twice whilst I ran errands.... No issues at all.


    Then I had a thought, at some point over the weekend my car was knocked by some one causing a little damage to the bumper (I posted up in the general discussion sub-forum about it)... Maybe that triggered the alarm and we just didn't hear it (the folks have new double glazing and it cuts out a remarkable amount of noise) and caused a drain (if the horn/lights) are flashing.

    I still need to get it tested whilst it's running... I have a digital multimeter somewhere but no idea where. If I can find that I can at least test the charging circuits are working fine... engine running with lights on should read around 13.8v as already mentioned by @jimjams
     
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  13. Heckler Top Contributor ★ ★ ★ ★ ☆

    I've done half a dozen short trips of less than 2 miles in the last 48hrs, constant stop start mostly with lights, wipers and heating turned on... Car has shown no signs of draining since last Monday.

    I'm starting to wonder if I had left something on now... I'm sure I didn't, but starting to second guess myself now.
     
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