Dim ingnition warning lamp
Posted: Fri Nov 02, 2012 10:54 am
Hi all,
My 1967 saloon had an alternator fitted by a previous owner and for the past 7 years it has given no trouble. The control box is present on the bulkhead but is discnnected entirly save for the earth wires.
Just recently i noticed that the ignition warning lamp is glowing very dimly at all engine speeds. I have a voltmeter fitted to the dash and this reads around 13.5volts at fast idle with no accesories switched on as it always has since i fitted the gauge.
The battery seems to stay charged and the car starts readily enough.
At night with halogen lamps, heater, stereo, and wipers where necessary swiched on, all seems normal and she'll start the next morning ok.
However, over the past two years on very rare occasions i have found the car to be completely flat; ie; the battery has been dead. Initially this was down to the nine year old battery which died suddenly and i replaced, and then the new one packed in within a year due to a dodgy cell; and was replaced under warranty. When i had the same trouble again, i did a parasitic drain test and found that some current was being drained off by the stereo. With the stereo disconnected there was no drain showing on the meter and after a week or two I changed this for another stereo and have had no further trouble with flat batteries since August.
Now i am wondering if the root cause of all this was actually the alternator.
The car is in regular use and the flat battery problem in the past has only occurred after the car has been left for three or four days while i used my other Morris or my Austin.
If the lamp is glowing this points to the alternator doesn't it, but the red light comes on normally and goes out when starting, but instead of going out completely it just glows very faintly. When switching off, it will flare up before the engine dies, which seems normal.
Any thoughts?
My 1967 saloon had an alternator fitted by a previous owner and for the past 7 years it has given no trouble. The control box is present on the bulkhead but is discnnected entirly save for the earth wires.
Just recently i noticed that the ignition warning lamp is glowing very dimly at all engine speeds. I have a voltmeter fitted to the dash and this reads around 13.5volts at fast idle with no accesories switched on as it always has since i fitted the gauge.
The battery seems to stay charged and the car starts readily enough.
At night with halogen lamps, heater, stereo, and wipers where necessary swiched on, all seems normal and she'll start the next morning ok.
However, over the past two years on very rare occasions i have found the car to be completely flat; ie; the battery has been dead. Initially this was down to the nine year old battery which died suddenly and i replaced, and then the new one packed in within a year due to a dodgy cell; and was replaced under warranty. When i had the same trouble again, i did a parasitic drain test and found that some current was being drained off by the stereo. With the stereo disconnected there was no drain showing on the meter and after a week or two I changed this for another stereo and have had no further trouble with flat batteries since August.
Now i am wondering if the root cause of all this was actually the alternator.
The car is in regular use and the flat battery problem in the past has only occurred after the car has been left for three or four days while i used my other Morris or my Austin.
If the lamp is glowing this points to the alternator doesn't it, but the red light comes on normally and goes out when starting, but instead of going out completely it just glows very faintly. When switching off, it will flare up before the engine dies, which seems normal.
Any thoughts?