mk2 mike Posted February 14, 2015 Report Posted February 14, 2015 Morning all! I've got an electrical question I'm hoping one of you boffins will be able to answer for me. [emoji106] although it's not an OSF question! I've just bought an absolute piece of crap Fiesta Mk4 as a cheap runaround and also something to block the garage door with. Anyway my issue is with the battery going flat overnight. When I first bought the car last week and got it home it sat outside for four days without being used, when I went to start it it started on the button first time (in fact the best I've ever had a car start!). I used it to pick the girlfriend up from work, got home parked up and the next morning the battery was completely flat. I just assumed I'd left something on, lights etc so I checked everything was off and charged the battery. The next morning it was flat again [emoji35] I couldn't understand how it been sitting for four days and yet the battery was fine but yet when now it flattens itself overnight. I've had a little look around it this morning, and when running the battery is charging and showing 14.4 Volts so I know the alternator is okay so I assume there must be a drain on the battery somewhere that happened since I drove it. I've started to look around the car and found that's now the rear wiper does not work. it did when I drove it the other day as it was raining and I was using it. Could it be that this fault with the rear wiper is causing the battery to draining overnight? I don't have a Haynes manual but looking on the Internet it appears there is no separate fuse for the rear wiper so therefore I cannot just remove a fuse. Not sure thing if you're familiar with this model car but the way the rear hatch Electrics work is by having contacts on the inner sill of the boot: And also matching contact points on the inside of the hatch lid And when the boot is closed the two touch and obviously supply electricity to the rear wiper and heated screen etc. As I said earlier this car was only used mainly as something to block the garage and and a bit of extra security for the Escort so I'm not fussed about having a working rear wiper. So am I right in thinking that if I cover over the contacts with electrical tape and stop power going into the tailgate it'll cure the drain? (Assuming the wiper motor is the problem).
dalmarshall Posted February 14, 2015 Report Posted February 14, 2015 It might be a knackered battery mike. Try charging it and not connecting it back up to the car...does it still go flat. Parasitic drains are a pain to locate!
DT36 Posted February 14, 2015 Report Posted February 14, 2015 Could be a Parasitic drain. Disconnect the battery earth and put a multimeter on amps between the earth lead and battery neg post. If something is on and drawing a current, you will see the reading on the meter. The trick now is to locate the fuse box or fuse boxes (not sure how many) and pull one fuse at a time. If the reading on the meter drops down after pulling a fuse on the circuit, then this will point you in the right direction to the drain. With regards to the boot lid and diagnosing the heated window and wiper, opening and closing the boot should be the same as pulling a fuse. i.e. if you open the boot and the current on the meter drops, then it could be one of these 2. However, remember to pull the boot interior light bulb out before doing this, as you'll get a current reading going up as the bulb comes on. A lot of times when you can't see the cause it can be the glove box or more so the boot interior light. 3 Series E36 BMWs were a git for this.
mk2 mike Posted February 14, 2015 Author Report Posted February 14, 2015 Mine is a poverty spec so no boot or glove box lights. [emoji13] I'm just confused how it was ok, now suddenly is playing up. And the rear wiper has stopped working at the same time. Wiper switch? I'll try the amp test later and charge the battery overnight. Thanks for the replies so far, 2 more things to try!
mk2 mike Posted February 14, 2015 Author Report Posted February 14, 2015 No idea why the pictures aren't showing above! The contact points in the boot:
skeeter Posted February 14, 2015 Report Posted February 14, 2015 I had a similar problem with my LC and after many frustrating days of trying to work out what it was I decided to get an auto electrician in. He found the problem in a couple of minutes, and it turned out to be the boot light. For some reason, the light was coming on when the boot was closed and going off when it was open. The very simple stop gap solution was to remove the bulb and then get him back to sort it properly. Might be worth checking things like that, for example does the interior light work, is it off? Failing that, find a mobile auto electrician and save your sanity. S 2
Tackleberry Posted February 14, 2015 Report Posted February 14, 2015 I know exactly what it is.... It's your OSF using black magic...thinking you're being a judas... Remember the film Christine? Be afraid, be very afraid. 1
SmokeEm Posted February 14, 2015 Report Posted February 14, 2015 I know exactly what it is.... It's your OSF using black magic...thinking you're being a judas... Remember the film Christine? Be afraid, be very afraid. Agreed. It wants to be green not orange 1
mk2 mike Posted February 14, 2015 Author Report Posted February 14, 2015 Which setting do I put it on for amps? Not got a clue lol
irishtorag Posted February 14, 2015 Report Posted February 14, 2015 Mike the switch set 0n the lower panel has a habit of melting and causing the boot light to make contact with earth or the wiper connection depending on how badly its melted if indeed that is the problem, Replaced lots of them when I worked for ford dealer every one the same
mk2 mike Posted February 14, 2015 Author Report Posted February 14, 2015 I don't have a boot light. Or a glove box light! Sorry mate what switch set on which lower panel?
DT36 Posted February 14, 2015 Report Posted February 14, 2015 Which setting do I put it on for amps? Not got a clue lol ImageUploadedByTapatalk1423930538.109048.jpg Swap the red lead over into the 5A jack. Put your dial there. DO NOT measure any voltage with the meter in this position. Disconnect the battery negative and only measure in series. 1
DT36 Posted February 14, 2015 Report Posted February 14, 2015 Send me a PM with your email. I have a guide on basic electrics that might help you. 1
irishtorag Posted February 14, 2015 Report Posted February 14, 2015 not on the tailgate Mike but on the tailgate slam panel the contact set 1
mk2 mike Posted February 14, 2015 Author Report Posted February 14, 2015 Gotcha. How do I remove that? Can't see any fixings!
irishtorag Posted February 15, 2015 Report Posted February 15, 2015 screw driver each side two small metal clips will fall out then but u can push them back in
mk2 mike Posted February 15, 2015 Author Report Posted February 15, 2015 Cracking. I'll take a look later. Thanks for all your advice guys. Much appreciated. [emoji106]Really wish I knew how to fix stuff like this! 1
DT36 Posted February 15, 2015 Report Posted February 15, 2015 Cracking. I'll take a look later. Thanks for all your advice guys. Much appreciated. [emoji106]Really wish I knew how to fix stuff like this! Did you get my email, Mike?
mk2 mike Posted February 15, 2015 Author Report Posted February 15, 2015 No mate. Nothing has come through yet!
DT36 Posted February 15, 2015 Report Posted February 15, 2015 No mate. Nothing has come through yet! Check your spam box. It has left my end, but I will re-send.
mk2 mike Posted February 15, 2015 Author Report Posted February 15, 2015 Right a little update which has confused me even more! I took the battery out to charge it. (Multimeter said 12.7 volts) put it on the charger and the 'fully charged' light came on within about 60 seconds. (Multimeter still showed 12.7 volts). Put it straight back on the car and it started instantly! So to check the battery as Dalmarshall said above, I disconnected the battery and left it overnight to see if it drained. I checked it just now, multimeter showing 12.3 volts. Connected it up but car won't start, starter turned s few times then got the familiar click click click. Battery now shows 12.1 volts on multimeter. Should this still be enough to start the car? I did the test as Dt36 suggested, the multimeter showed 0.10 throughout every fuse removal. No change at all. Also noticed the rear wiper (that didn't work at all yesterday) now works on the switch but doesn't park. It just stops wherever you turn the switch off. (It used to park a few days ago). I'm really confused. Any ideas?
katana Posted February 15, 2015 Report Posted February 15, 2015 Think the battery is goosed! or at least one cell probably is. A good battery should hold full charge for at least a couple of weeks disconnected - 1/2v drop in 24hrs ....not good. Trying to turn a cold engine with a depressed battery is unlikely to be successful unless you catch it right first crank - starter will probably pull voltage down to 9 - 10v so everything suffers particularly the ignition! 2
mk2 mike Posted February 15, 2015 Author Report Posted February 15, 2015 Someone suggested putting the lights on while cranking. If the lights dim it points to the battery. Just tried it and it cranks but the lights don't dim. I'm on the verge of scrapping it. The car is only worth a few hundred quid so getting a mobile electrician out wouldn't be economically viable. [emoji20]
DT36 Posted February 15, 2015 Report Posted February 15, 2015 Right a little update which has confused me even more! I took the battery out to charge it. (Multimeter said 12.7 volts) put it on the charger and the 'fully charged' light came on within about 60 seconds. (Multimeter still showed 12.7 volts). Put it straight back on the car and it started instantly! So to check the battery as Dalmarshall said above, I disconnected the battery and left it overnight to see if it drained. I checked it just now, multimeter showing 12.3 volts. Connected it up but car won't start, starter turned s few times then got the familiar click click click. Battery now shows 12.1 volts on multimeter. Should this still be enough to start the car? I did the test as Dt36 suggested, the multimeter showed 0.10 throughout every fuse removal. No change at all. Also noticed the rear wiper (that didn't work at all yesterday) now works on the switch but doesn't park. It just stops wherever you turn the switch off. (It used to park a few days ago). I'm really confused. Any ideas? Mike, what was the letter after the 0.10 ? Was it an A or was it mA ? If it was mA, then ignore everything below: If it was 0.10A, then this is too high. Anything over 25 to 50 mA is too much and can drain your battery. Make sure the ignition is switched off and don't attempt the test for about 10 mins to let any modules go to sleep. Did you also observe the meter amperage when opening and closing the tailgate. If so, did the reading change? Additionally, can you also try the same test, but this time pull out the relays individually. What can sometimes happen is that a relay can stick and it will get a constant feed to the coil. If the meter reading drops when you pull the relay, this could be faulty. Lastly, having checked all the previous, undo the big wire at your alternator. Sometimes you get a shorted diode that can cause current to flow through the alternator's power cable via the shorted diode and into the case, through the bolts and back to the negative battery terminal. This will drain a battery a bit sharpish. Again, check the reading on the meter before and after. As Katana has stated, could be a weak cell in the battery that is just staring to fail. This usually manifests itself during cranking. However, when the cell totally fails you will get a reading in the morning of around 10v, as each lost cell is worth 2v. But, if you've read this far, then you had a reading of 0.10A, so you still have a drain somewhere to find... Good luck, as this white mans magic is all witchcraft and can be a right pain in the backside...
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