Battery death immeadiately
Thread Starter
Heel & Toe
Joined: May 2020
Posts: 15
Likes: 0
Battery death immeadiately
Hi,
I have new battery, but every day I have to charge. After 100km I switch off the car and again start is impossible. Can it make radio relay? I think, that will be starter, but I will be glad to listen yours advice.
C4 1986 Convertible.
Thank you
I have new battery, but every day I have to charge. After 100km I switch off the car and again start is impossible. Can it make radio relay? I think, that will be starter, but I will be glad to listen yours advice.
C4 1986 Convertible.
Thank you
Advanced
Joined: Jul 2020
Posts: 52
Likes: 12
From: Upstate NY
You need to check to see if the battery is being charged by the alternator. Easiest way I've found to do this is to take a voltage reading across the battery with the car running and then shut the car off and take another reading. If the voltage doesn't drop by ~0.5 volts or more from running to shut off, or the running voltage is below ~12.7 volts while running, you have something wrong in your charging circuit.
I would also check that the battery bolts are both tight and not stripped out, its fairly easy to over-tighten the battery bolts and strip them, causing the battery to make a poor connection.
I would also check that the battery bolts are both tight and not stripped out, its fairly easy to over-tighten the battery bolts and strip them, causing the battery to make a poor connection.
Last edited by finn_the_flying_fox; Aug 7, 2020 at 02:38 PM.
Safety Car
Joined: Aug 2009
Posts: 3,752
Likes: 276
From: Melbourne, Victoria, Australia
Hi
As mentioned check the alternator is charging your battery, the voltage should go from 12v to 14v when starting the car depending on battery charge.
Next check for any abnormal power draw, i have found the antenna can be a problem if it retracts and does not break the switch.
Listen for a click every now and then near the antenna, if it has not opened the contacts the motor o/load can click on and off every minute or so.
That can flatten a battery quite quickly, over a few days when parked.
Check the charge cable from alternator to battery is a good circuit, i think from memory it goes via the starter to battery.
Fusable links can fail, check with a multimeter the alternator is charging.
Check at alternator + and engine ground -, then check at battery + to ground -.
If a battery has been completely and rapidly drained, the plates can buckle and will never be the same again.
so check 12 volts and is holding charge, then start car should go up 13 / 14 volts and the alternator is good.
If not charging then the alternator may have failed.
Good luck
As mentioned check the alternator is charging your battery, the voltage should go from 12v to 14v when starting the car depending on battery charge.
Next check for any abnormal power draw, i have found the antenna can be a problem if it retracts and does not break the switch.
Listen for a click every now and then near the antenna, if it has not opened the contacts the motor o/load can click on and off every minute or so.
That can flatten a battery quite quickly, over a few days when parked.
Check the charge cable from alternator to battery is a good circuit, i think from memory it goes via the starter to battery.
Fusable links can fail, check with a multimeter the alternator is charging.
Check at alternator + and engine ground -, then check at battery + to ground -.
If a battery has been completely and rapidly drained, the plates can buckle and will never be the same again.
so check 12 volts and is holding charge, then start car should go up 13 / 14 volts and the alternator is good.
If not charging then the alternator may have failed.
Good luck
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Battery
1.You might try disconnecting the alternator battery lead overnight, if alternator has a Bad diode, battery will Not go dead.
2. Run a voltmeter to battery.
pull fuses one at a time and watch voltage.
the pulled fuse will allow the battery voltage To stop going down.
3. Behind the battery take off the fusible links and put an ammeter between the Fusible link and connection point.
when the ammeter moves off zero, that is the bad leg of wiring/ items
2. Run a voltmeter to battery.
pull fuses one at a time and watch voltage.
the pulled fuse will allow the battery voltage To stop going down.
3. Behind the battery take off the fusible links and put an ammeter between the Fusible link and connection point.
when the ammeter moves off zero, that is the bad leg of wiring/ items
Last edited by coupeguy2001; Aug 8, 2020 at 11:46 PM.
