Battery/Electric Woes

[andeh]

Right, first post and a bit of a long one, but hoped you guys might be able to help me out with some battery/electric woes I think I am having.


Background

Not been using my bike much over the Autumn/Winter period, only a few sporadic journeys.

I went for a mid-week ride back in November, having not taken it out for a few weeks. Trip was about 30m return. I had the phone (sat nav) charging and both the lights and heated grips on full blast, so drawing a fair bit of power. Tried to start it a few days later and found the battery to be dead.

Did a full charge on the battery, took it out for a ride the following week, 120m or so. About 30m in I noticed a fluctuation with the speedo needle, it gradually got worse and by the 60m mark the needle was going crazy, doing 360’s and in no way related to the speed I was doing. On the way home the problem had spread to the tachometer needle and about 2 miles from home I had the lights flickering (including the dash, although the clock/odometer stopped displaying digits, but remainder back lit), engine stuttering and then cut out completely. After playing with the ignition some I managed to get it started and back home. Checked the battery and the screws had worked quite loose, suspect I hadn't put them on tight enough when I’d re-fitted the battery and they’d worked loose, which may have caused the above symptoms?

Took the battery out, trickle charged for a week, back in the bike on the Sunday, took it out the following Saturday. Started fine first time, tried to re-start after fueling up at the local garage (<1m) and the bike wouldn't start as the battery is dead again. Jump start off a mate got me going again, after a 15m trip I was able to start again on my own, then again after another 15m trip (so assume alternator and reg/rec are working?). Took the battery into the local dealer (only bought it Jan ’13) to check it was holding charge and they spotted no problems…

I’d taken it out again weekend before last, stuck it in the bike Tuesday, wired it to ONLY the bike electrics, tested it again yesterday (i.e. it’d  been stood 6 days) and it was still showing 12.80.


Problem

I finally had the time to spend a good few hours tinkering with it last night at a mates, found my multimeter was faulty which didn't help, but got some rather odd findings which I’m unsure whether or not are related to any of the above:

• With only the multimeter connected to the battery, it was showing 12.86.
• With the battery hooked up to the bike, but running multimeter in series (i.e. multimeter bridging the connection between negative terminal on battery and negative cable from bike) it was showing 11.5 – with the ignition off and keys out.
• With the multimeter in series and ignition on it jumped to 12.83.

This surprised me, I've no alarm, immobilizer or anything I can think of that would still be drawing power with the ignition off, so I expected the reading should be 0, which is what my mates ZZR600 was showing when we tested his for comparison. To try and isolate the cause I removed each of the fuses in turn and found when I removed the 5A Back up fuse the reading dropped from 11.5 to 0.25, still not 0 but closer… Having checked the Haynes, Owner’s Manual and done some Internet searching I can’t find anything that clearly explains what the Back Up circuit is for, one post suggested it was for the speedo, but I rode home with the 5a fuse removed and the speedo was working fine(?).

Whilst I was fiddling I also tried taking readings with and without the accessories fitted and the readings came back the same, which (I think) suggests there isn't a problem with any of them having a parasitic draw.

Bike is a 2001 FZR600, 30k miles on the clock and just had its major service. I've had it from 11k and other than the down pipes rusting through and a new chain, it's been reliable and virtually trouble-free. In terms of addons/accessories:

• Headlight mod, few years ago now, not touched the wiring since and seems to be working fine
• Scottoiler, but V not E, so doesn't go near the electrics
• Oxford heated grips, but they’re the ones with the unit that is supposed to shut them off if the ampage gets low so they don’t drain the battery. I also soldered the positive wire from them into the ‘bus bar’ (I think that's what it's called), at the bottom of the fuse box, so they shut off anyway when I turn off the ignition.
• Charger for iPhone, from Ultimate Addons, is waterproof with rubber caps on the connectors, wired directly to the battery, also has the auto shut off technology I believe
• USB charger, female socket with a waterproof cap which I keep under the seat, also wired directly to battery terminals
• Micro USB Charger for the Drift, also waterproof, but usually kept under the seat anyway when not in use

I’m going to pick up a new multimeter later this week and do some more thorough testing over the next week or two. I think I’m also just going to try riding it a bit, as I’ve not had chance to much lately, and see if there are ‘still’ any problems, although will make sure I’ve got a buddy with me and some jump leads… I'm also wondering whether I should leave/test the bike with or without the 5A Back Up fuse connected. However, I wondered if any of you had any thoughts on the above, particularly around the power drain on the Back Up circuit and whether that is normal?


Thanks in advance

[Fazerider]

12.8v after a week in the bike sounds fine, but I'd move the various chargers you have to a circuit that goes off with the ignition unless it's essential to have them powered all the time.
You say they're wired direct to the battery, I trust you have a fuse in the circuit (as close to the battery as possible)!


The odometer, specifically the trip meter, is the circuit that draws a tiny amount of power when the ignition's off. Making series voltage measurements isn't usually useful, modern multimeters have a very high impedance so something drawing a millionth of an amp will be enough to register near to the battery voltage.


Before taking it for another spin, examine all the wiring and connectors, especially those in the charging circuit. A very fine screwdriver or a filed down staple of the beefy kind used to secure cardboard boxes makes a good tool for freeing connectors from their housings so they can be tightened with a squeeze from some pliers. You want to feel some resistance as you push them together.


A check of the battery voltage with the engine running will tell you if the charging system is working. At 5000rpm it should generate enough to supply heated grips and lights and push enough current into the battery to get the terminals up to at least 13.8v. With no electrical load and max engine revs the battery voltage shouldn't rise up much beyond 14.8v.

[andeh]

Thanks for the reply Fazerider, some useful information in there, especially about the trip meter and connecting in series.


All the chargers I've got wired up have inline fuses, wasn't aware distance from the battery mattered though, but they are all pretty close. I might take a look at wiring everything into the ignition directly, but direct to the battery was the easiest option at the time and I think for the ignition I'd need to drill some screws out(?), I'll check the Haynes...


I did have the tank up yesterday and had an eye ball of the connectors that were visible around that area, nothing untoward jumped out, but didn't have the Haynes on me at the time so wasn't as thorough as I had liked. I'll do as you suggest and dig out the wiring diagram for the charge circuit.


I had checked the battery voltage when the engine was running @ 5k revs sometime last month and it seemed fine, but do need to double check that when the new multimeter gets here.


Re the 11.5 reading on the Back Up circuit, would you suggest that between the trip meter draw and multimeter impedance that it isn't something I need to worry about then?

[Fazerider]

Fuses: people often think they are there to protect the bit of equipment that they are attached to. In fact, the fuse is also to protect the cable. If the supply wire gets chafed and starts shorting to ground you're relying on the fuse to cut the power before the wire gets red hot and sets things alight. The length of wire between the battery and fuse is not protected so you want it to be as short (and well-insulated) as possible.


Yes, I'd ignore that 11.5v reading.


Another measurement I'd try is to take a look at the battery voltage with the engine not running and then turn on the headlights. If the voltage plummets in a few minutes to 12v or less then it is knackered regardless of what your dealer told you. (Five minutes powering both headlight bulbs should use about 10% of a fresh, fully-charged battery's capacity.)