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19th January 2021, 17:33 | #11 | |
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It's probably not the battery that's failing but the way in which you are testing it.-- There are 6 cells in a battery.--Each one will give about 2.1 volts.--( six times 2.1 is 12.6 in total. ) If you would like to read a bit more about batteries then go to the thread on the main page that says---Really, really useful information.--I have three posts in there about batteries and their funny little ways.----Go have a read under the name of COLVERT. |
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19th January 2021, 19:26 | #12 | |
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19th January 2021, 19:37 | #13 | |
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Last edited by Gizmo150; 19th January 2021 at 19:38.. Reason: Clarity |
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19th January 2021, 21:42 | #14 |
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If it is low pump pressure it's most likely to be the HP pump or the sensor connection on it.--
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19th January 2021, 23:35 | #15 |
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Reading all the posts on this, I have a feeling that you have over-discharged the battery to below 8v by constant short charge times followed by draining it trying to start the car. Even when in this state it can still show 13v but won’t hold it long enough to start or keep the car running.
Sorry to say but it is looking like your only solution is to replace the battery as there is a good chance now that the one you have on the car has a buckled plate.
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20th January 2021, 17:52 | #16 | |
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Since the 20 mile drive yesterday afternoon, the car successfully started twice in the evening and twice today. Start and end of daughter's NHS shift. I will check the battery again on Saturday when the car is here. I've checked the battery every day since I started this post and not recorded a voltage lower than 11.7v. Would 8v destroy the key coding as suggested by COLVERT? |
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22nd January 2021, 22:52 | #17 | |
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23rd January 2021, 11:37 | #18 | |
I really should get out more.......
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CHARGE the battery for 24 hours, then leave it disconnected for 1 hour then measure voltage, it should read at least 12.5V, start car and check voltage with engine running, should be 14.4V +, switch lights on, radio, demister and check again, should be near 13.8v any significantly lower readings, need a new battery, and your alternator is probably in need of attention, new regulator pack?. Good luck. |
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23rd January 2021, 12:28 | #19 | |
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Thank you. Just to clarify, with engine running the terminal readings are 13.8v. With battery disconnected after an hour it reads 12.3v. With battery connected to car and a spare battery attached in parallel it reads 12.6v. the increase in voltage makes no difference to the cranking time before the engine will run. With the engine ticking over there's 13.8v. with headlights on it's still 13.8v. add rear screen demister it's 13.7v and adding climate control it's down to 13.6v and that at tick over speed. With revs increased to 1800 rpm I've turned everything on and the voltage is steady at 13.8v That's lower than I'd like and probably indicative of the alternator but not necessarily the starting problem. I just tried an inline amperage test. There is a current draw of 0.34 amps. So I'm currently ( no pun intended) pulling fuses. Under bonnet fuse box: F8 removed value drops to .29a. with fuse back in and disconnecting the connectors on top of diesel heater the value drops to .14a. cleaning and reconnecting it remain at .14a. so still have a .14 current draw. Current draw is now .02a. I can deal with that. Last edited by Gizmo150; 23rd January 2021 at 16:21.. Reason: Update |
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23rd January 2021, 13:36 | #20 | |
I really should get out more.......
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