alternator or battery??

[GQ Bear]

Just this week my battery gauge has been showing 14v when i start car and then progressively loses voltage as i drive down to around 9-10v. Sometimes it will jump back up to 14v for no apparent reason.

Last night on way home from work it went as low as 6-7volts. Lost power to radio but luckily headlights still worked. Parked in driveway, switched off and battery was dead when tried to restart.

Jump started car this morning and started, but lost voltage again as i drove.

Please help. Could it be bearing, maybe?? Belts are tight and nothing drawing load, no shorts that i'm aware of.

Alternator was recoed only about 12mths ago. Battery's less than 2yrs old.

Thanks
Bear

[shakes]

have you got acess to a multimeter(voltmeter) ?

with the motor running put the meter in series with the charge cable from the alt, will show if it's charging out not.

if not drop in to most auto elec or battery resellers and they can do it for ya to try make a sale.

Simon

[GQ Bear]

Will try that on Monday.

If i continue to drive it will low voltage can i stuff anything? It's efi.

[Cossie]

have you got acess to a multimeter(voltmeter) ?

with the motor running put the meter in series with the charge cable from the alt, will show if it's charging out not.

if not drop in to most auto elec or battery resellers and they can do it for ya to try make a sale.

Simon

you mean in parallel. Series will fry the multimeter.


Check all the Earth leads from battery to motor and body.chassis etc. A crap earth will give these problems.
Also check the wire from the back of the alternator to the battery, this could be corroded or half broken. While your at it, check all the wires going to the alternator.

If the above are all good it looks like new alternator time

[GQ Bear]

Jump started it this morning and drove to work with 12-14v all the way. Maybe crappy terminals?? Hit it with CRC yesterday.

[NutterGQ]

more likely diodes in the alty

[drivesafe]

Jump started it this morning and drove to work with 12-14v all the way. Maybe crappy terminals?? Hit it with CRC yesterday.

Hi GQ Bear, as posted above, it sounds like a bad connection, most likely a bad earth but check all connections, positive and negative and don’t just spray all the connections.

You need to physically inspect every connection and permanently fix any faulty connections or to rule them out as being the problem.

Cheers.

[GQ Bear]

Jump started it this morning and drove to work with 12-14v all the way. Maybe crappy terminals?? Hit it with CRC yesterday.

Hi GQ Bear, as posted above, it sounds like a bad connection, most likely a bad earth but check all connections, positive and negative and don’t just spray all the connections.

You need to physically inspect every connection and permanently fix any faulty connections or to rule them out as being the problem.

Cheers.

Yeah will do this today after work. raining yesterday