Xploding_S3
Registered User
Hi Guys
If this thread or issue was covered before , can you please direct me to it.
A breakdown to my issue,
Symptoms and issues :
Battery light is on for a few months.
Car starts and runs well, so I ignored it,
A month back , I started the car and it drained the battery,
I sent the battery for charging , refitted it , started the car and found the car was running on the battery.
Did some test - found no charge was getting to the battery , I traced it to the fuse, no issues with the fuse(Fuse box on battery for alternator), I took out the fuse , cleaned(white stuff on it), fitted it and now i was getting charge over it.
More testes:
took of the alternator for testing , ran it on the bench and got a reading of 14.2v, all seemed fine,
fitted it back to the car.
Cold start - reading at the battery was 14.08v at the alternator - Battery 14v.
car warms up , load increases and this reading drops - Alternator +- 13.7v and battery 13.8v.
With the lights on im getting 13.6v at the alternator.
Belt on the car is less then a year old as well, got it after buying a new battery.
Battery light still remains on and the battery is less then a year old, and has been tested a month ago,
I found i was losing 0.1v when doing drop test so i added a new 4g cable from the alternator to the battery fuse box, 4g cable from the fuse box to the positive post,
4g cable from the negative post to the gearbox , 4g from the gearbox to the head.
small improvements when the car is warm, less voltage drop.
however im still getting the battery light and im still finding readings around 13.6v to 13.8v.
Areas i need to look at - regulator , ecu signal to the alternator or alternator clutch?
help please,
Im worried if i change the alternator then it could be the ecu,
so if you know how to test that signal, that will help.
alternator is a bosch 120a - fuse on the car is a 150a
If this thread or issue was covered before , can you please direct me to it.
A breakdown to my issue,
Symptoms and issues :
Battery light is on for a few months.
Car starts and runs well, so I ignored it,
A month back , I started the car and it drained the battery,
I sent the battery for charging , refitted it , started the car and found the car was running on the battery.
Did some test - found no charge was getting to the battery , I traced it to the fuse, no issues with the fuse(Fuse box on battery for alternator), I took out the fuse , cleaned(white stuff on it), fitted it and now i was getting charge over it.
More testes:
took of the alternator for testing , ran it on the bench and got a reading of 14.2v, all seemed fine,
fitted it back to the car.
Cold start - reading at the battery was 14.08v at the alternator - Battery 14v.
car warms up , load increases and this reading drops - Alternator +- 13.7v and battery 13.8v.
With the lights on im getting 13.6v at the alternator.
Belt on the car is less then a year old as well, got it after buying a new battery.
Battery light still remains on and the battery is less then a year old, and has been tested a month ago,
I found i was losing 0.1v when doing drop test so i added a new 4g cable from the alternator to the battery fuse box, 4g cable from the fuse box to the positive post,
4g cable from the negative post to the gearbox , 4g from the gearbox to the head.
small improvements when the car is warm, less voltage drop.
however im still getting the battery light and im still finding readings around 13.6v to 13.8v.
Areas i need to look at - regulator , ecu signal to the alternator or alternator clutch?
help please,
Im worried if i change the alternator then it could be the ecu,
so if you know how to test that signal, that will help.
alternator is a bosch 120a - fuse on the car is a 150a
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