[Guna]

Very valid point. if a car can have all kind of indicators, some of which may not result in immediate problem, why something which is as basic as battery condition not have an indicator.
On 2 occasions, I could not start my Honda City AT and I had to call the helpline. When I was trying to explain the problem over phone to the technician I was very sure that it was not battery problem because according to me the 'battery malfunction' sign should have been blinking in that case (all signs were flashing in this case). Only if there was a gauge/indicator (just like the fuel gauge) which told me to switch off the fan blower or turn off music when the engine was off!

[1100D]

Originally Posted by PearlJam

Yes, we need some logic like that, and I'm sure it's not rocket science to come up with something!

It will also be quite useful. Have known the situations when a vehicle did not start in the morning, having to wonder whether its a light-on/short circuit drain, bad alternator or the battery itself.

Trying to recall the last usage for signs of alternator having gone kaput, does not help. The alternator might be working but not appropriately (not enough voltage under full load).

Now if the alternator warning can be made inclusive of inappropriate functioning, then we can surely pinpoint a small short circuit or the battery (even a small short circuit, light on condition can be made to be sensed and indicated)

So there will be three things

1> Alternator warning - already present - but make it sense minor malfunctioning

2> Short circuit/"lights on" drain - additional (would sense any additional amperes than normal flowing out of the battery for an extended period while the car is locked/static)

3> Battery under voltage

[PearlJam]

@pganapathy, a simple voltmeter is not enough. An almost dead battery will still show the correct voltage but will not be able to drive the required current.

Originally Posted by 1100D

So there will be three things

1> Alternator warning - already present - but make it sense minor malfunctioning

2> Short circuit/"lights on" drain - additional (would sense any additional amperes than normal flowing out of the battery for an extended period while the car is locked/static)

3> Battery under voltage

A short circuit indicator is a separate topic altogether! In majority of the cases, a battery dies just normally due to it's lifespan. The catch is, this lifespan could be anywhere between 2 years to 3.5 years (for a diesel) and 2.5-4 years (for a petrol). From what I heard, diesel car batteries last a little less than petrol ones.

[abhijitvp]

I faced excatly same situation in my Vdi. But when I asked SA about this he immediately told me to check battery. He told me that it's a low battery indicator. I checked my battery outside and replaced it.

[PearlJam]

Looks like all they need to do is, provide an indicator that checks for malfunction of other indicators and presume that it's a battery problem

[Aroy]

After contemplating for quite some time on the "battery problem", I feel that a problematic battery is difficult to identify, except by testing it on load (and that is when the car refuses to start).

Normally the battery without load gives a fairly consistent voltage, so at stand still or while getting charged the battery voltage by it self would not indicate any problem. It is when the voltage drops below the threshold value while starting that the problem start. In a non ECU vehicle a battery which can rotate the engine would normally start it, and there after the alternator takes over. It is in ECU based vehicles that the extreme low voltage creates random ECU glitches. In my opinion better voltage regulators to the ECU is required to prevent random firing of warning lights.

Of course if ECU is programmed to check the battery voltage each time the vehicle is started, then it can identify a failing battery by referring to the voltage drop table calibrated for a range of temperatures and other parameters. (and now you have to reset it each time you change the battery)

[PearlJam]

Originally Posted by Aroy

After contemplating for quite some time on the "battery problem", I feel that a problematic battery is difficult to identify, except by testing it on load (and that is when the car refuses to start).

The ECU could still record the voltage drop during starting, and warn if there is a significant drop in voltage or driving current. However, we could be in a catch-22 situation here - during starting if the voltage drops below a certain level, the ECU itself will malfunction. And that is the time you expect the ECU to do the measurements!

So I agree, the ECU should be made to work across a wider range (similar to our mobile phone battery chargers). If that is done, shouldn't it be fairly easy to identify voltage drop or driving current during starting?

[sumeethaldankar]

In our 1984 Premier Padmini we had a voltage indicator meter connected to the battery. (i am not sure what is was called).This meter was squarish device with a center dial and a needle with values above a + and - sign.Whenever the battery/dynamo were fine the needle would always hover around the "+" sign while accelerating and at idle however if there were any issues with the battery/dynamo it would hover below close to the "-" sign.

Now i am not sure if this was actually related to the battery or just the dynamo but whenever it was found close to the negative mark the car would later on have a problem with the battery or the with the charging.

I even try to find such device for my oldie 800 but was never able to procure one.

[Aroy]

Originally Posted by sumeethaldankar

In our 1984 Premier Padmini we had a voltage indicator meter connected to the battery. (i am not sure what is was called).This meter was squarish device with a center dial and a needle with values above a + and - sign.Whenever the battery/dynamo were fine the needle would always hover around the "+" sign while accelerating and at idle however if there were any issues with the battery/dynamo it would hover below close to the "-" sign.

Now i am not sure if this was actually related to the battery or just the dynamo but whenever it was found close to the negative mark the car would later on have a problem with the battery or the with the charging.

I even try to find such device for my oldie 800 but was never able to procure one.

That is an ammeter - measuring current.
- Positive = current flowing to the battery (charging)
- Negative = current flowing out of battery (discharging)

Many of us also had a Voltmeter - normally calibrated upto 16V.

Most of these instruments were useful when the car had a Dynamo (DC generator). With advent of Alternators, one does not need the meters as much as an indication of whether the battery is being charged (no light) or discharged (red light) for normal running. Of course meters make life interesting as you have more data to ponder on.

[Sutripta]

Originally Posted by sumeethaldankar

In our 1984 Premier Padmini we had a voltage indicator meter connected to the battery. (i am not sure what is was called).This meter was squarish device with a center dial and a needle with values above a + and - sign.
......
I even try to find such device for my oldie 800 but was never able to procure one.

Hi,
That will be an ammeter. Easily available, cheap. Not really necessary for your Maruti.

Some discussions
http://www.team-bhp.com/forum/techni...ml#post2598782
and
http://www.team-bhp.com/forum/4x4-ve...ml#post2588002
and I'm sure on lots of other threads in this forum.

Regards
Sutripta