Unkel Kunkel Posted February 19, 2020 Report Share Posted February 19, 2020 Do you like a mystery? Here is a tale of a problem that frustrated me for some months. Something was completely flattening the battery overnight, but only intermittently about every 2 -3 months.Between times it was absolutely fine and could be parked for a week and start instantly.It started to get more frequent. Checked all the usual sources of current drain.Nothing. Did a check to see if draining current - normal limits after the car locked and all systems shut down.So something was happening but only now and again.For most of the time it was absolutely fine. OBD11 code reader - nothing showed up. Would there be a point taking it to an auto electrical place? - but it might be there for a fortnight or even a month and be absolutely fine. So I continued to try without out a fuse for things like radio, locking etc.No progress. One summer night I drove home, locked the car and as I walked to the house I thought I could hear a very very slight whine from the car.(It was barely audible so I knew I hadn’t locked mother in law in the car..).Odd -never noticed that before. I came back an hour later and it was still seemed to be doing it - or was I imagining it? I called my missus over.She couldn't hear it , sighed and went in doors, leaving me crawling around the locked car trying to locate where it was coming from. Weirdly, it didn’t seem to be coming from under the bonnet. But that night .. the mystery was finally solved.Can you guess what was happening ? To be continued- 2200 hrs tomorrow. Link to comment Share on other sites More sharing options...
poppyman Posted February 19, 2020 Report Share Posted February 19, 2020 Central locking pump running? Tony. Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 9 hours ago, poppyman said: Central locking pump running? Tony. No, not the central locking,Tony Link to comment Share on other sites More sharing options...
Nick Jones Posted February 20, 2020 Report Share Posted February 20, 2020 Fuel lift pump “priming”........ Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 20, 2020 Report Share Posted February 20, 2020 addblue recycle pump running ? Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted February 20, 2020 Report Share Posted February 20, 2020 The radiator fan on my 306 used to run for 2 or 3 minutes after the ignition was switched off, but it was supposed to. Except that time I found it still running hours later, I had to disconnect fuses to stop it. 306s were nice cars, but always wiring problems! Still the radiator fan was pretty noisy so I doubt that's Van's problem. Doug Link to comment Share on other sites More sharing options...
poppyman Posted February 20, 2020 Report Share Posted February 20, 2020 Folding roof pump? Sounds like some kind of pump? Tony. Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 Car incidentally, 2 litre FSI. Link to comment Share on other sites More sharing options...
Simons3 Posted February 20, 2020 Report Share Posted February 20, 2020 Radio/changer not sleeping? Link to comment Share on other sites More sharing options...
Colin Lindsay Posted February 20, 2020 Report Share Posted February 20, 2020 30 minutes ago, Simons3 said: Radio/changer not sleeping? That's a possible; some of them lose the ability to talk to the CANbus and take an age to shut down, if ever they do. Happens a lot with replacement radios. (I gave up trying to fit an aftermarket unit to a Ford recently, too many connections) Another common problem is the ignition switch failing to turn everything off, so something like the heater blower fan will continue to turn very gently - hence the slight whining - and so flatten the battery. Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 (edited) Strangely, the slight noise seemed to be coming from here, (Offside rear wheel) To be continued.... Edited February 20, 2020 by Vanadium23 corrected, wrong side of car Link to comment Share on other sites More sharing options...
Colin Lindsay Posted February 20, 2020 Report Share Posted February 20, 2020 You can't have air suspension fitted.... AND you don't have rotating wheel trims either.... Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 no air suspension, Colin - Sport suspension. & no fancy wheel trims... Link to comment Share on other sites More sharing options...
NonMember Posted February 20, 2020 Report Share Posted February 20, 2020 Is that a tyre pressure monitor on the valve? I note that's also where the filler cap is. Back when I first started at Rover, the then-new 214 models used to make a weird mooing noise (just very quiet but you could hear it out in the country) for a while after being driven. That was the fuel tank breather valve opening to stabilise pressure. It didn't happen on later models as the evaporative loss control system ("purge canister") meant the offending valve got deleted. Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 1 hour ago, NonMember said: Is that a tyre pressure monitor on the valve? I note that's also where the filler cap is. Back when I first started at Rover, the then-new 214 models used to make a weird mooing noise (just very quiet but you could hear it out in the country) for a while after being driven. That was the fuel tank breather valve opening to stabilise pressure. It didn't happen on later models as the evaporative loss control system ("purge canister") meant the offending valve got deleted. Yes, there is a TyrePal monitor .... but it’s not that. Yes, there is a fuel filler flap with solenoid release ....but it’s not that - or the tank breather. Link to comment Share on other sites More sharing options...
Clive Posted February 20, 2020 Report Share Posted February 20, 2020 Electric handbrake? Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 20, 2020 Report Share Posted February 20, 2020 parked on a nail in the tyre will make a noise but .....wont flatten the battery Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 20 minutes ago, clive said: Electric handbrake? Nope.. just an ordinary handbrake... To chase it, I jacked the car up and ended up removing the wheel ... Link to comment Share on other sites More sharing options...
poppyman Posted February 20, 2020 Report Share Posted February 20, 2020 Abs sensor? Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 30 minutes ago, poppyman said: Abs sensor? No, It had nothing to do with the wheel - or the brakes. The first puzzle was where this odd sound was coming from. The next puzzle why it was doing what it did. And final problem was how to put it right. All will revealed soon.. Link to comment Share on other sites More sharing options...
Simons3 Posted February 20, 2020 Report Share Posted February 20, 2020 Alarm siren Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 Sorry a bit late ! Firstly, Nick - you got the closest! That odd sound was coming from the plastic fuel tank! It wasn’t that full , so maybe it was a bit more resonant. These cars have a fuel pump in the tank. Although the ignition was off and the car double locked - It had not switched off and was vigorously pumping away and steadily flattening the battery. Not some old fashioned on/off thing like wot God intended, but a pump whose output depends on the frequency of repeatedly switching on and a square wave current influenced by the engine demands etc. The tank is under the floor, under the rear seat Removing the rear seat I found this a ” Fuel pump control Module “ -and it felt very, very warm. Now 3 hours on, the battery was flat. I replaced the black box. All solved. It had kept me awake at nights. That was nearly three years ago. Absolutely fine since...so far. My missus mused -“Why do you think the car had a brand new battery when we bought it? Do you think they knew there was a problem?” She is probably right - of course. - I kept my thoughts to myself - what would have happened if we had been involved in a crash and the pump had continued to merrily pump petrol over us... Link to comment Share on other sites More sharing options...
Anglefire Posted February 20, 2020 Report Share Posted February 20, 2020 There should (well there will be) an inertia trip switch on the pump circuit- but whether it is a hardwired or software trip would only be clear from giving the wiring diagrams a good coat of looking at. Unfortunately these days they seem to be designed to be unreadable 😂 Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted February 20, 2020 Author Report Share Posted February 20, 2020 2 minutes ago, Anglefire said: There should (well there will be) an inertia trip switch on the pump circuit- but whether it is a hardwired or software trip would only be clear from giving the wiring diagrams a good coat of looking at. Unfortunately these days they seem to be designed to be unreadable 😂 That’s reassuring. I have now got to sort out the missus’s C Max’s “ smart charging “ problems - which aren’t. Link to comment Share on other sites More sharing options...
poppyman Posted February 20, 2020 Report Share Posted February 20, 2020 Strange one that for VW? Mercedes have a problem with wiring burning out on the in tank fuel pump..... They never catch fire they just stop. I hate moderns. Tony. Link to comment Share on other sites More sharing options...
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