Battery Light coming up on low rpm

kavesh55 · 25th November 2008, 16:34

Dear All,

This is regarding a problem, with a friends car, which I was using.
The Battery light on the dash used to light up as the car used to idle. (The idling rpm is not abnormally low) .
On giving some accelerator, the light used to go off. Its worse with the headlamps on. In case of no accelerator, the car used to stall.
I think its a faulty alternator not charging up on low rpms.

Gurus pls advice on the fault.

vikram_d · 25th November 2008, 16:40

If the alternator is faulty then typically it should not charge even at high rpms. But you have mentioned that accelerating a little stops the problem. Dont think it is an alternator issue.

Shashank.A · 25th November 2008, 16:55

what were the Idle RPMs ?

Perez · 25th November 2008, 17:06

Hi Kavesh55

I had the same problem with my M800 sometime back. It was the alternator that needed attention. Once that was done the problem automatically disappeared.

Regards
perez

white_vdi · 25th November 2008, 17:14

kavesh what car is it and year?

howler · 25th November 2008, 17:17

check battery leads if they are properly tightened and correct idle rpm.

trrk · 25th November 2008, 17:23

Hi,

Slipping alternator belt?

vikram_d · 25th November 2008, 17:29

Slipping alternator belt would have caused a screeching sound. Dont think that is the cause as he would have noticed it.

Ajaybiz · 25th November 2008, 17:36

Weak dioads, weak rectifier, worn out carbon brushes or even short coils inside dynoma get it checked.

kavesh55 · 25th November 2008, 18:11

Quote:

Originally Posted by Perez

Hi Kavesh55

I had the same problem with my M800 sometime back. It was the alternator that needed attention. Once that was done the problem automatically disappeared.

Regards
perez

what was the attention given, mean what replacements were done ?

Quote:

Originally Posted by Shashank.A

what were the Idle RPMs ?

Does not have a tacho, so dont know. but have driven the car before and the issue never cropped up.

Quote:

Originally Posted by white_vdi

kavesh what car is it and year?

its a 1993 M 1000

kavesh55 · 25th November 2008, 18:13

Quote:

Originally Posted by vikram_d

Slipping alternator belt would have caused a screeching sound. Dont think that is the cause as he would have noticed it.

you are right, no belt slipping here.

could it be a alternator issue of a lesser degree, thats why charging at higher rpms.

esteem_lover · 25th November 2008, 18:13

Quote:

Originally Posted by kavesh55

Dear All,

This is regarding a problem, with a friends car, which I was using.
The Battery light on the dash used to light up as the car used to idle. (The idling rpm is not abnormally low) .
On giving some accelerator, the light used to go off. Its worse with the headlamps on. In case of no accelerator, the car used to stall.
I think its a faulty alternator not charging up on low rpms.

Gurus pls advice on the fault.

Replace your alternator. Nothing else will do. Believe me, i know these symptoms

Sudipto-S-Team · 25th November 2008, 18:27

Get the alternator checked by Bat Mobile from Exide. If they say the alternator is not working properly, get it serviced or replace the rectifier or replace the whole damn alternator. The costs respectively are around Rs 350, Rs 1200 and Rs 6000 in Calcutta. Don't know about your city. Best of luck. But do get the battery guys to test the alternator first. It's free.

25th November 2008, 16:34	#1
kavesh55 BHPian Join Date: Nov 2007 Location: Mumbai Posts: 748 Thanked: 49 Times	Battery Light coming up on low rpm Dear All, This is regarding a problem, with a friends car, which I was using. The Battery light on the dash used to light up as the car used to idle. (The idling rpm is not abnormally low) . On giving some accelerator, the light used to go off. Its worse with the headlamps on. In case of no accelerator, the car used to stall. I think its a faulty alternator not charging up on low rpms. Gurus pls advice on the fault.
	() Thanks

25th November 2008, 16:40	#2
vikram_d Senior - BHPian Join Date: Jul 2006 Location: Bangalore Posts: 2,427 Thanked: 1,185 Times	If the alternator is faulty then typically it should not charge even at high rpms. But you have mentioned that accelerating a little stops the problem. Dont think it is an alternator issue. Last edited by vikram_d : 25th November 2008 at 16:56.
	() Thanks

25th November 2008, 16:55	#3
Shashank.A BHPian Join Date: Sep 2007 Location: New Delhi Posts: 484 Thanked: 10 Times View My Garage	what were the Idle RPMs ?
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25th November 2008, 17:06	#4
Perez BHPian Join Date: Sep 2008 Location: Bangalore Posts: 56 Thanked: Once View My Garage	Hi Kavesh55 I had the same problem with my M800 sometime back. It was the alternator that needed attention. Once that was done the problem automatically disappeared. Regards perez
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25th November 2008, 17:14	#5
white_vdi BHPian Join Date: Sep 2008 Location: new delhi Posts: 857 Thanked: 38 Times View My Garage	kavesh what car is it and year?
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25th November 2008, 17:17	#6
howler BHPian Join Date: Aug 2008 Location: coorg/bangalore Posts: 447 Thanked: 570 Times	check battery leads if they are properly tightened and correct idle rpm.
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25th November 2008, 17:23	#7
trrk Senior - BHPian Join Date: Feb 2004 Location: Alleppey, Kerala Posts: 2,114 Thanked: 34 Times View My Garage	Hi, Slipping alternator belt?
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25th November 2008, 17:29	#8
vikram_d Senior - BHPian Join Date: Jul 2006 Location: Bangalore Posts: 2,427 Thanked: 1,185 Times	Slipping alternator belt would have caused a screeching sound. Dont think that is the cause as he would have noticed it.
	() Thanks

25th November 2008, 17:36	#9
Ajaybiz BANNED Join Date: Nov 2004 Location: Bangalore Posts: 1,440 Thanked: 320 Times View My Garage	Weak dioads, weak rectifier, worn out carbon brushes or even short coils inside dynoma get it checked.
	() Thanks

25th November 2008, 18:27	#13
Sudipto-S-Team Senior - BHPian Join Date: Jun 2007 Location: Kolkata Posts: 1,320 Thanked: 290 Times View My Garage	Get the alternator checked by Bat Mobile from Exide. If they say the alternator is not working properly, get it serviced or replace the rectifier or replace the whole damn alternator. The costs respectively are around Rs 350, Rs 1200 and Rs 6000 in Calcutta. Don't know about your city. Best of luck. But do get the battery guys to test the alternator first. It's free.
	() Thanks