Mitsubishi Battery Drain

[GamLing]

My car is a Mitsubishi G-Wagon. I have had starting problems for the last few days. I bought a new battery as I thought that this was the problem but apparently not, as the car wouldn't start the morning after the new battery was fitted. I recharged the battery and then disconnected both cables immediately and left the car standing overnight. Next morning, after reconnecting the cables, the car started instantly.

So, I left the car for another 24hours with the battery cables connected and when I tried to start it the next morning, the battery was completely flat again.

Someone suggested that my car has a short which is draining the battery. How do I go about solving problem ..... or does anyone know of any auto-electrical companies (good ones) in the Pattaya area? I would be prepared to spend a few days in BKK or Chonburi or Sattahip or Rayong just to get my car reliable again.

The car has a voltmeter (standard equipment from Mitsubishi) and would that give me a clue as to where the problem lies?

Thank you..... I hope someone can help me.

[transam]

Had a similar problem once and it was an alternator fault causing the drain. Remember the alternator is connected to the battery 24/7.

[GamLing]

HI Transam,

You've got me thinking now. What do you make of these voltage readings?

Over the last week or so, the Mitsubishi voltmeter has indicated a reading of around 13.5 volts with every consumer switched off and the engine revs at about 2000 r.p.m. On letting the engine idle at about 900 r.p.m the reading drops to about 12.2 to 12.5 volts. When I switch on the air con and all lights, the reading falls to below 12 volts.... sometimes as low 11 volts.

However, this was not happening all of the time initially but seems to be there all of the time now......... at least when I can start the car!!!

[jombom]

When your engine is running, you should be seeing 13 or 14 volts on your voltmeter, assuming your alternator is working properly.

You almost definitely appear to have a drain somewhere.

If you travel on Pattaya Tai towards Sukhumvit, and turn left at Sukhumvit, there are a couple of auto-electrical shops within 50 mtrs. Some of the guys working there are fairly good.

[Semper]

Had a similar problem once and it was an alternator fault causing the drain. Remember the alternator is connected to the battery 24/7.

Hmmm. The alternator should sharge the battery not drain it. Never heard of this but I'm no expert on electric things What I think the OP should do, is to check the cable from the battery to starter motor (the connection at the starter).

If this is an old car, it could be the starte solenoid.

[transam]

HI Transam,

You've got me thinking now. What do you make of these voltage readings?

Over the last week or so, the Mitsubishi voltmeter has indicated a reading of around 13.5 volts with every consumer switched off and the engine revs at about 2000 r.p.m. On letting the engine idle at about 900 r.p.m the reading drops to about 12.2 to 12.5 volts. When I switch on the air con and all lights, the reading falls to below 12 volts.... sometimes as low 11 volts.

However, this was not happening all of the time initially but seems to be there all of the time now......... at least when I can start the car!!!

There is an internal voltage regulator in the alternator which could be the prob.

[transam]

Had a similar problem once and it was an alternator fault causing the drain. Remember the alternator is connected to the battery 24/7.

Hmmm. The alternator should sharge the battery not drain it. Never heard of this but I'm no expert on electric things What I think the OP should do, is to check the cable from the battery to starter motor (the connection at the starter).

If this is an old car, it could be the starte solenoid.

If the alternator has an internal prob it can drain the battery when motor not in use, had it happen.

[GamLing]

When the battery is charged again the car starts immediately. I can't see the starter motor, or the solenoid, being at fault.

I think that Transam's diagnosis is worth following up

Edited to suggest my next step re. checking alternator.

[Semper]

When the battery is charged again the car starts immediately. I can't see the starter motor, or the solenoid, being at fault.

I think that Transam's diagnosis is worth following up

Edited to suggest my next step re. checking alternator.

Yes, but I think the op did this one time only. Could be an coincidence. However he could charge the battery and disconnect the cables to the alternator and try to start after 24 hours.

[Semper]

GamLing - please post an update when you have fixed the problem I will by TA a couple of beers if it's the alternator that's draining the battery.

[transam]

GamLing - please post an update when you have fixed the problem I will by TA a couple of beers if it's the alternator that's draining the battery.

Cheers .

Just a note, if the earth lead is at fault it will get hot/warm to the touch when cranking the engine as the fat earth and positive leads are big for one reason, to carry big amps to the starter.

[GamLing]

I promise that I will post an update and I hope that it will be soon........... living where I do without wheels is a real problem. Motorcycle taxis are OK for short distances and when it's not raining.

[cali4995]

to check for a battery drain you would: 1) disconnect one of the battery terminal leads 2) connect one end of a 12v test lamp to the battery and the other end to the lead (you can also do this with a VOM and measure amperage) if there is a parasitic drain with the engine off and ignition key removed, the lamp will glow (dull or bright depending on amount) usually it is something like an aftermarket car stereo installed improperly or a car alarm, something "on" even when key turned-off. a dome light left on is another example. rarely is it like a shorted diode in the alternator or some other mysterious "short" on a circuit. you need to approach this with a chess-like strategy or you can easily spend all day looking for it. removing fuses one at a time to isolate circuits. you need a list of probable causes and you simply work down the list checking items off. as you stated you had a starting problem, it may be possible you have a problem with your actual starter motor and it is giving symptoms resembling that of a dead battery. this is what the auto shop will look for. just giving you a brief outline. you need to establish what is given 1) good battery 2) properly operating charging system (if that is indeed the case) 3) terminals and cables secure and in good condition.4) functioning starter.

and then you begin looking for the more unlikely scenarios. your unknowns in this particular problem. working down your probability list.ah,mis-spent youth.

[GamLing]

GamLing - please post an update when you have fixed the problem I will by TA a couple of beers if it's the alternator that's draining the battery.

Good news for me but not so good news for Semper!!!

The 'parasitic drain' was located by the local Mitsubishi workshop. Not the battery, not the battery cables, not the radio. not the alarm system, not the ignition switch. The culprit was the alternator!!!!! Diode problem and although the alternator was charging the battery when the engine was running, it was causing a severe drain when the car was parked overnight.

An auto-electrics shop (recommended by jombom) fitted a brand -new looking but reconditioned alternator and my car starts instantly now after parking all night. It's quieter also!!

So, transam, enjoy those couple of beers from Semper and thank you for the heads-up.

[transam]

GamLing - please post an update when you have fixed the problem I will by TA a couple of beers if it's the alternator that's draining the battery.

Good news for me but not so good news for Semper!!!

The 'parasitic drain' was located by the local Mitsubishi workshop. Not the battery, not the battery cables, not the radio. not the alarm system, not the ignition switch. The culprit was the alternator!!!!! Diode problem and although the alternator was charging the battery when the engine was running, it was causing a severe drain when the car was parked overnight.

An auto-electrics shop (recommended by jombom) fitted a brand -new looking but reconditioned alternator and my car starts instantly now after parking all night. It's quieter also!!

So, transam, enjoy those couple of beers from Semper and thank you for the heads-up.

Made my day, Cheers.

PS. It's good that guys let us know the out come to probs, really helps for future prob thoughts.

[Semper]

GamLing - please post an update when you have fixed the problem I will by TA a couple of beers if it's the alternator that's draining the battery.

Good news for me but not so good news for Semper!!!

The 'parasitic drain' was located by the local Mitsubishi workshop. Not the battery, not the battery cables, not the radio. not the alarm system, not the ignition switch. The culprit was the alternator!!!!! Diode problem and although the alternator was charging the battery when the engine was running, it was causing a severe drain when the car was parked overnight.

An auto-electrics shop (recommended by jombom) fitted a brand -new looking but reconditioned alternator and my car starts instantly now after parking all night. It's quieter also!!

So, transam, enjoy those couple of beers from Semper and thank you for the heads-up.

Made my day, Cheers.

PS. It's good that guys let us know the out come to probs, really helps for future prob thoughts.

Ok. I owe you a couple.

[GamLing]

Ok. I owe you a couple.

I owe transam a couple of beers also

[cali4995]

to clarify, a basic charging system test showing amperage output / voltage at a specified rpm would

show the alternator was not performing properly. "Or" using the test light method as described and

disconnecting the suspect alt. with ignition off and key removed. it need not be a guessing game.

as was stated you need to establish: 1) good battery 2) properly operating charging system (if that

is indeed the case) 3) terminals and cables secure and in good condition.4) functioning starter.

as given knowns in your problem before looking elsewhere for mysterious parasitic electric drains.

[GamLing]

So, the big question that's bothering me is........................ do I fit a new original unit from Mitsubishi or do I buy a reconditioned unit from any one of the many "shop house" places scattered along the Sukhumvit Road in Pattaya. A new unit is about twice the price of a reconditioned one but I have to consider a number of factors, such as:

1. The cost, obviously
2. The quality of the work
3. The expected life of a new unit vs a reconditioned one
4. Comparison of warranties
5. Can I be sure that a "shop house" reconditioned replacement is just that
6. My car is 9 years old and I am 70 years old. It will surely be my last car so, should a new original unit be my choice?

Please help me to decide guys, I trust your judgement and advice. Transam and Semper, what do you think? Thank you.

[transam]

So, the big question that's bothering me is........................ do I fit a new original unit from Mitsubishi or do I buy a reconditioned unit from any one of the many "shop house" places scattered along the Sukhumvit Road in Pattaya. A new unit is about twice the price of a reconditioned one but I have to consider a number of factors, such as:

1. The cost, obviously
2. The quality of the work
3. The expected life of a new unit vs a reconditioned one
4. Comparison of warranties
5. Can I be sure that a "shop house" reconditioned replacement is just that
6. My car is 9 years old and I am 70 years old. It will surely be my last car so, should a new original unit be my choice?

Please help me to decide guys, I trust your judgement and advice. Transam and Semper, what do you think? Thank you.

To be honest there is little to go wrong in an alternator. They replace a couple of troublesome bits, test and sell. Recon OK. Little money and away you go.

[Lickey]

Since alternators were introduced into the car world, they have been known to be a major battery drain if the diode goes bad, in the good old days with a dynamo, the cut-out box/regulator would totally disconect the battery from the dynamo, these days, a good garage will look for things like a courtesy light staying on, perhaps in the boot or under the bonnet, something you cant see,,

OP, you could have just changed the brush/diode box for about 20quid, but reading your post saying your Mitsubushi is now quieter, it seems like the alternator bearings were worn out to,

A general rule of thumb for belt tension is half inch either way on 1 foot of belt, less will affect the bearings, more will induce slip, also if the belt has sunk into the pulley, ie, the pulley is shiny right to the center, its time for a new belt,

You have done the right thing, replace it with a recon, but please check the belt tension, Thais always seem to think more is better,

Cheers, lickey.

[filguy]

Exactly the same problem. after 2 to 3 days, the battery is drained, the car wont start but i can see there is still battery charge left. I went to ACT to replace the battery bought 8 months ago. They gave me spare. But still the battery drained after 3 days.

i dont know if alternator problem or what. i have to get back to ACT

[GamLing]

Exactly the same problem. after 2 to 3 days, the battery is drained, the car wont start but i can see there is still battery charge left. I went to ACT to replace the battery bought 8 months ago. They gave me spare. But still the battery drained after 3 days. i dont know if alternator problem or what. i have to get back to ACT

In my case, the battery drain was so immense that nothing electrical would work after standing overnight. Even the interior lights wouldn't come on. Could be leakage to earth within the alternator!!!! Almost 4 months since the alternator was replaced on my car and no problems since.

[filguy]

Exactly the same problem. after 2 to 3 days, the battery is drained, the car wont start but i can see there is still battery charge left. I went to ACT to replace the battery bought 8 months ago. They gave me spare. But still the battery drained after 3 days. i dont know if alternator problem or what. i have to get back to ACT

In my case, the battery drain was so immense that nothing electrical would work after standing overnight. Even the interior lights wouldn't come on. Could be leakage to earth within the alternator!!!! Almost 4 months since the alternator was replaced on my car and no problems since.

Hi GamLing, how much you spent for alternator?

[GamLing]

Hi GamLing, how much you spent for alternator?

I was quoted 8,500 baht for new 90 amp/Hr alternator from the local Mitsubishi dealer..... not including fitting time but fitting time was estimated to be no more than 30 minutes.

Hitachi Automotive (Bangkok) quoted 5,500 baht for Hitachi new 90 amp/Hr. Delivery from Bangkok to Pattaya 3 hours and fitting free.

Reconditioned 90 amp/Hr alternator obtained and cost me 3,200 baht. No charge for fitting but only 30 days warranty. Fortunately, it is working perfectly and output well over 13 volts.

[transam]

Alternators are not thrown away, little to go wrong, usually the internal regulator, so most replacements are just recons. Easy money.

[filguy]

Hi GamLing, how much you spent for alternator?

I was quoted 8,500 baht for new 90 amp/Hr alternator from the local Mitsubishi dealer..... not including fitting time but fitting time was estimated to be no more than 30 minutes.

Hitachi Automotive (Bangkok) quoted 5,500 baht for Hitachi new 90 amp/Hr. Delivery from Bangkok to Pattaya 3 hours and fitting free.

Reconditioned 90 amp/Hr alternator obtained and cost me 3,200 baht. No charge for fitting but only 30 days warranty. Fortunately, it is working perfectly and output well over 13 volts.

Thanks.

[GamLing]

Hi, it's me again!

I'm now having a similar problem related to starting my Mitsubishi after standing all night. But, this time, I think it could be related to the battery. I bought a new battery in January this year, think my original starting problems were battery-related. This was found to be not the case and the culprit was caused by battery drain through the alternator. A new alternator fixed that.

The new alternator is still pushing out around 13.5 volts but the car won't start in the morning now. During my earlier problems, the new battery took a hammering for about a month or more......... charging from total discharge and then losing charge and the process continued like that until the alternator was replaced. Fast charge/boost charge/trickle charge/jump start....... you name it and it was done.

The battery electrolyte level has never needed to be topped up and there is a scum noticeable on the electrolyte surface now. I have tried disconnecting the earth cable temporarily overnight after charging the battery but, next morning, the engine will not start again.

Please....... any comments on the lack of need for topping up and the slight scum on the electrolyte surface? Also, do you think my newish battery has died after the hard life it had earlier this year?

My thanks to all.

[transam]

Sounds like your dodgy alternator ''cooked'' your battery . You are now charging OK but the battery perhaps will not accept the charge.

[GamLing]

Sounds like your dodgy alternator ''cooked'' your battery . You are now charging OK but the battery perhaps will not accept the charge.

Hi Transam. The battery shop where I bought this particular battery in January says that the battery is OK.................. but they would wouldn't they!!!! I watched them do the check and the hydrometer readings were a bit "iffy". The float was on, or close to, the "red" zone" on two of the cells but shaking the hydrometer dropped the float to the "green zone". But ....TIT!!!