Electrical Fault ?

[centrico]

I completed a 500 km round trip on Wednesday with no problems night time and day time driving.

Recently had the swinging are bushes replaced - in case it is relevant.

Last night [Thursday] and today, I was driving along and the air con unit slowed / lost power. The headlights dimmed but did not go out. The engine lost power but did not cut out. The CD player kept playing up too. This happened intermittently.

The charge light stayed off or I might have suspected the alternator.

I have checked the battery leads and they are tight. The battery has plenty of water and is charged.

I have run the car with the air con off in case that was the problem.

Any ideas what the problem is before I take the car to the garage, please? I don't want them giving me a load of BS

edit for added info.

Edited May 8, 2010 by centrico

[NADTATIDA1]

Trans is your man....he will b here soon!

[fredob43]

More than likely the alternator, the light only need's a little bit of power and out it go's. Get the peep's in the main garage to test it.

[Hssl]

alternator or poor earthing would be my guess

[WarpSpeed]

Unfortunately the reality is if electrical problems were that easy to diagnose then every one would be technicians. There's a hundred things that can cause similar problems and near impossible to diagnose on a net forum with so little info..

JFYI been a first rate automotive technician for more then 20 years now and I have no idea what a "swinging are bush" is? Doesn't sound electrical though..

[yeesipha]

Unfortunately the reality is if electrical problems were that easy to diagnose then every one would be technicians. There's a hundred things that can cause similar problems and near impossible to diagnose on a net forum with so little info..

JFYI been a first rate automotive technician for more then 20 years now and I have no idea what a "swinging are bush" is? Doesn't sound electrical though..

swing arm bush maybe..... lower front wishbone bush maybe.... not electrical anyway.

[centrico]

Unfortunately the reality is if electrical problems were that easy to diagnose then every one would be technicians. There's a hundred things that can cause similar problems and near impossible to diagnose on a net forum with so little info..

JFYI been a first rate automotive technician for more then 20 years now and I have no idea what a "swinging are bush" is? Doesn't sound electrical though..

swing arm bush maybe..... lower front wishbone bush maybe.... not electrical anyway.

Was a typo. Apologies. Yes, swinging arm bushes (wishbone).

Seems I'd better get the alternator checked then. I was flashing like crazy on the way home tonight. Happy I did not have my Mac on

[stingray]

Auto electrics are a nightmare for sure. Check you battery earth lead to chassis/body,not just the battery end, and there is also a big earth lead that goes from chassis to engine or gearbox (important), just in case the work you had done they moved stuff. Daft thought but is the alternator drive belt tensioned OK. Other than that get the alternator checked out. If you have a meter, check the battery terminals between pos and neg, should read around 12.5 volt, then start the engine and read again, should read around 13.5 volts. Then turn on lights and air con etc and take a reading, the alternator should be able to keep up. Good luck.

12.5 Volt at idlespeed, all lights and AC on. When engine reves up it should go over 13 Volt. If it's a Bosch alternator is schould be over 14 Volt during driving. I allways say tha can not trust the alternator light. Every private car i drive i fit in a Volt Meter in to see allways the voltage. If it comes below 12 Volt, than it not charge enought. Of corse checking all the terminals and earts as well. Check your alternator belt as well if it's not lose (it could slipping). Sometime terminals are corroded unvisible. Take them off and clean, respectively spill them with real hot water and all the corrosion is gone imidently. Before reconecting the Batterie terminals put grease on the battery terminals first. Check the earth cable of your engine block. Check eart whiring of body or chassis.

Fitting in a Voltmeter is easly around your dash or somewhere in the console. Can also buy a digital Voltmeter for stick in the cigarette lighter, cost about 650 Baht. So you can elimnate faults easly.

[WarpSpeed]

Unfortunately the reality is if electrical problems were that easy to diagnose then every one would be technicians. There's a hundred things that can cause similar problems and near impossible to diagnose on a net forum with so little info..

JFYI been a first rate automotive technician for more then 20 years now and I have no idea what a "swinging are bush" is? Doesn't sound electrical though..

swing arm bush maybe..... lower front wishbone bush maybe.... not electrical anyway.

Was a typo. Apologies. Yes, swinging arm bushes (wishbone). Oh ok, in that case there is no reason why it should be effecting any of your electrical but TiT

Seems I'd better get the alternator checked then. I was flashing like crazy on the way home tonight. Happy I did not have my Mac on

In that case sounds like it but if that is the case then your info about a fully charged battery could not have been accurate as it was being drained and low due to the faulty alternator and why you were having voltage drop offs that affected your system. Stinger is correct you should be reading more then 13 volts it could as much a 14 depending on alternator, regulator settings, load and voltage requirements at the time, say for example if your battery is already low it should be at maximum voltage even at idle..

Ironically I just diagnosed my neighbors Ford Escape for him as he was having a similar issue on a new battery and a 4 month old alternator, his technician suggested it was his battery cable(?) for what reason is beyond me, but I tested it with my volt meter and told him otherwise as it was only at 12 volts and in discharge mode while running so no way it was working properly, so he brought it to the dealer and they replaced the alternator no charge as it was under warranty.. Problem solved, he was very happy (well not having to have it replaced, but that he was able to go armed with the facts about the problem and he got it solved)..

Edited May 9, 2010 by WarpSpeed

[chris5346]

hello,

how you getting on with your fault ?

are you in chiang mai ? i'll take a look for you,

if you had some work done last week maybe they disconnected a battery or alternator cable and didn't put it back very well and that's causing your voltage drop.

what car is it and how old is it ?

[Gary A]

I had a Suzuki Carribian that had similar problems. It was in and out of a Bangkok Suzuki dealership a number of times and they claimed to have fixed the problem each time. They DIDN'T. I was coming home from work and it quit running altogether. Fortunately I was in front of a little mom and pop repair shop. I didn't have much confidence in them to say the least. When a 14 year old boy came out with a flashlight converted to a continuity tester and started working on it, I walked up the road to a small store and had several beers. When I went back the kid handed me a corroded multipoint connector and wanted 90 baht for the repair. Since the car started and had no more symptoms, I gave him 200 baht, thanked him and never had a problem after that.

[Sisaketmike]

Trans is your man....he will b here soon!

1. Use o Voltmeter; hold it outside at the battery clamps. You should have at least 13.5 volts, or higher when the engine is running.

2. Is that okay check the battery without running engine, you should have at least 12.2 or more volt.

3. Is that okay take off the clamps, clean them inside, it happens often and can be very dangerous when driving in the night. All will switch off, also your light.

4. Your battery is divided in 6 a' 2 volt cells, one might be broken. A so called 'acid lifter' will show if the cells are okay. (Not all shops have that!!!)

5. Next would be the + (plus = red) connection from battery to mostly starter, or starter relay. Check the connection. Is that okay please also check the – (minus) cable. A poor connection would cause problems like that. Check the voltage at your starter, if the voltage is okay at your battery!

6. Check if the alternator light is on when you switch ignition on. As far as I understood the light will go off, when the engine is running.

7. Should your voltage at the battery be okay, check the voltage at your starter.

8. Be aware that most 'Chang Rot will replace your battery first, after that the starter. Try to do the tests and let me know, if you could handle that. It's really easy, just follow the steps.

Good luck.

Edited May 9, 2010 by Sisaketmike

[Sisaketmike]

Auto electrics are a nightmare for sure. Check you battery earth lead to chassis/body,not just the battery end, and there is also a big earth lead that goes from chassis to engine or gearbox (important), just in case the work you had done they moved stuff. Daft thought but is the alternator drive belt tensioned OK. Other than that get the alternator checked out. If you have a meter, check the battery terminals between pos and neg, should read around 12.5 volt, then start the engine and read again, should read around 13.5 volts. Then turn on lights and air con etc and take a reading, the alternator should be able to keep up. Good luck.

12.5 Volt at idlespeed, all lights and AC on. When engine reves up it should go over 13 Volt. If it's a Bosch alternator is schould be over 14 Volt during driving. I allways say tha can not trust the alternator light. Every private car i drive i fit in a Volt Meter in to see allways the voltage. If it comes below 12 Volt, than it not charge enought. Of corse checking all the terminals and earts as well. Check your alternator belt as well if it's not lose (it could slipping). Sometime terminals are corroded unvisible. Take them off and clean, respectively spill them with real hot water and all the corrosion is gone imidently. Before reconecting the Batterie terminals put grease on the battery terminals first. Check the earth cable of your engine block. Check eart whiring of body or chassis.

Fitting in a Voltmeter is easly around your dash or somewhere in the console. Can also buy a digital Voltmeter for stick in the cigarette lighter, cost about 650 Baht. So you can elimnate faults easly.

The voltage in idle speed should be higher than 12.5.

With running engine exactly 13.8 Volt, or even higher. You never check the voltage in your cigarette lighter, only if you can't lit up your cigarette.

It's not the earth cable, it's called minus-. The cable goes to the chassis. It can't be the alternator belt, because mostly more is attached to one belt, like power steering, or air con.

You can buy a Voltmeter for 379 baht at Tesco, if you don't know anybody.

Pleasse read my other post and follow the steps. Good Luck.

[Sisaketmike]

Unfortunately the reality is if electrical problems were that easy to diagnose then every one would be technicians. There's a hundred things that can cause similar problems and near impossible to diagnose on a net forum with so little info..

JFYI been a first rate automotive technician for more then 20 years now and I have no idea what a "swinging are bush" is? Doesn't sound electrical though..

swing arm bush maybe..... lower front wishbone bush maybe.... not electrical anyway.

Was a typo. Apologies. Yes, swinging arm bushes (wishbone).

Seems I'd better get the alternator checked then. I was flashing like crazy on the way home tonight. Happy I did not have my Mac on

I guess he meant the coals, which are attached to the REGULATOR at the ALTERNATOR. The regulator is attached with two screws, if anybody had changed them, it's also possible that the screws turned and the brushes don't touch the copper. Or not enough>

[centrico]

OK. I have read all the posts. I greatly appreciate the helpful answers.

As soon as I can I will go to the local shop and buy a voltmeter and run the tests as described.

I have checked the tension of the twin belts just now. They are fine.

Checked the battery cables again to make sure they are tight.

The battery cable connection to the alternator is tight. Also the one to the starter.

The altenator is visible from above. I can check the plug going into it after checking the voltage.

I am unable to see where the main chassis earth is as I cannot see where the cable goes to. One smaller earth goes to a connection next to the fuse box and that is OK.

Next is to get a voltmeter and do as described above, then I will post back. Hopefully tomorrow.

BTW it is a Nissan SR20 engine.

Chris5346. Not near Chiang Mai or I would have taken up that offer. But thanks for offering

[Sisaketmike]

OK. I have read all the posts. I greatly appreciate the helpful answers.

As soon as I can I will go to the local shop and buy a voltmeter and run the tests as described.

I have checked the tension of the twin belts just now. They are fine.

Checked the battery cables again to make sure they are tight.

The battery cable connection to the alternator is tight. Also the one to the starter.

The altenator is visible from above. I can check the plug going into it after checking the voltage.

I am unable to see where the main chassis earth is as I cannot see where the cable goes to. One smaller earth goes to a connection next to the fuse box and that is OK.

Next is to get a voltmeter and do as described above, then I will post back. Hopefully tomorrow.

BTW it is a Nissan SR20 engine.

Chris5346. Not near Chiang Mai or I would have taken up that offer. But thanks for offering

You have to remove the battery clamps to see the inside. Clean them. Check the lead as well !! Tighten it up. If you can't find the minus cable,(where it's going to) just try it with a jump wire! You just go from your minus contact at the battery to any ground, for example at the engine. You wrote a wire would go from the minus connection to the fuse box? That's plus then! (RED) The pole is bigger. Please contact me if you can't find the problem, I did electronic trouble shooting for German/American and Japanese cars. I had to learn all that crap, good luck.

[chris5346]

hi,

don't worry about the numbers at the moment just take a few reading and try to work out what's going on,

basically the battery is supposed to be around 12V and when the alternator is running that increases it to 13-14 V.

get a meter with crokodile clips if possible, place the red one on the pos + battery terminal and the black one on the minus - .

measure the d.c voltage reading and write it down - let us know.

start the engine and see if the reading goes up - write down let us know.

get someone to rev the engine up and down see what happens - write down any changes.

if you can change the meter from d.c to a.c and make a note of the maximum a.c voltage whist reving up and down - write down let us know.

put back to d.c and your looking for around 12 V again.

you can then move onto different parts of the wiring system to see how good your earthing is :

leave the red one on the battery and try the black one on all the negatives around the engine bay - exposed body metal work - body chassis, engine block, other earth cables etc they should all be around the same readings any lower voltage readings means maybe there's a bad connection/cable fault somewhere( you may need to remove the crocodile clip and hold on the probe - make sure you touch the probe to fresh clean metal and you should read the same voltage readings) - don't place the black probe on the positives like the fuses and 12V cable connections obviously.

maybe your alternator is breaking down when hot or under different load conditions - if your reading say 13-14V accross the battery switch on the headlights, main beam and blowers, window heater evrything and see what happens to the voltage reading.

you may get lucky and find a loose connection or a cable that's got hot etc that will point you in the right direction.

if your alternator is not increasing the voltage accross the battery then look at the alternator wiring connections maybe they are just weak if you can test the wiring around it - but you may need a circuit diagram and get some more info. - the fault is usually inside the alternator and you wont be able to find it - you can either replace the whole thing or get it reconditioned or just replace the regulator pack if your lucky - to test faulty alternator properly you need to take out and use different test equipment on a test rig.

but maybe your alternator is okay.

look forward to hearing how u get on,

chris

[stingray]

Auto electrics are a nightmare for sure. Check you battery earth lead to chassis/body,not just the battery end, and there is also a big earth lead that goes from chassis to engine or gearbox (important), just in case the work you had done they moved stuff. Daft thought but is the alternator drive belt tensioned OK. Other than that get the alternator checked out. If you have a meter, check the battery terminals between pos and neg, should read around 12.5 volt, then start the engine and read again, should read around 13.5 volts. Then turn on lights and air con etc and take a reading, the alternator should be able to keep up. Good luck.

12.5 Volt at idlespeed, all lights and AC on. When engine reves up it should go over 13 Volt. If it's a Bosch alternator is schould be over 14 Volt during driving. I allways say tha can not trust the alternator light. Every private car i drive i fit in a Volt Meter in to see allways the voltage. If it comes below 12 Volt, than it not charge enought. Of corse checking all the terminals and earts as well. Check your alternator belt as well if it's not lose (it could slipping). Sometime terminals are corroded unvisible. Take them off and clean, respectively spill them with real hot water and all the corrosion is gone imidently. Before reconecting the Batterie terminals put grease on the battery terminals first. Check the earth cable of your engine block. Check eart whiring of body or chassis.

Fitting in a Voltmeter is easly around your dash or somewhere in the console. Can also buy a digital Voltmeter for stick in the cigarette lighter, cost about 650 Baht. So you can elimnate faults easly.

The voltage in idle speed should be higher than 12.5.

With running engine exactly 13.8 Volt, or even higher. You never check the voltage in your cigarette lighter, only if you can't lit up your cigarette.

It's not the earth cable, it's called minus-. The cable goes to the chassis. It can't be the alternator belt, because mostly more is attached to one belt, like power steering, or air con.

You can buy a Voltmeter for 379 baht at Tesco, if you don't know anybody.

Pleasse read my other post and follow the steps. Good Luck.

At idlespeed is not fully charge possible, therefore only about 12.5 Volt. There is no Alternator who chages full at idle speed when all light, AC, electirc fans, etc. are on. Same i mention before 13. someting Volt at idlespeed maybe without AC or without lights. Minimum raves at 1300 to 1500 rpm the get at least 80% charge capacity of your alternator. Fully charge capacity at about 4 to 6'000 rpm on todays cars (up to 200 Amp for hevy cars. U can change a smaller poullie if you want. So Alterntator turns faster.

[VocalNeal]

One thing puzzles me or maybe I missed something. If the alternator is not putting out enough how does the OP start his car?

Many moons ago I had a car which had a similar lights on, lights off problem, back when cars had a thermal cut out in the wiring. Was supposed to be a safety feature which would have worked well but on a police car

Sounds like a loose or dirty connection.

[WarpSpeed]

^^Yeah, it depends on the alternator amperage output specs at low rpms, it's not general across the board.. Trucks for example are expected to work harder at lower rpms and therefore their alternators are spec'd to work harder under those circumstances as well the engines are usually larger or diesel and more capable of handling the extra load the lower rpms spec requires. Most diesels also charge at lower rpms as it takes more battery power to start them so quicker recovery is required...

^Well this is the question I brought up in that how was he getting any charge to recharge the battery, but if he is only getting a partial charge I.E. the voltage reg not working properly then maybe he could get enough charge driving during the day under lower loads to recharge but discharging under high loads.. The problem is most voltage regs these days are no longer located separately from or replaceable on the alternator but rather incorporated in them so he still has an alternator problem either way..

Edited May 11, 2010 by WarpSpeed

[stingray]

Beg to differ a little, my Vigo shows 13.5 at idle with stuff on but not in drive. But in case his system is not as good then he can get someone to rev the engine a bit of idle while he does the tests.

A Vigo is a Pick Up only. No additional electric fans, no ignition, etc. Normal cars have 2 electric fans at least and that's the "killer", because they run allways, when the air is on.

[centrico]

Update.

The car is now running smoothly again.

The altenator itself is fine. It was a wiring problem. Before I got chance to go to the shop to buy a voltmeter I jumped into the car and had no electrics at all on the dashboard when turning the ignition key.

Checked the fuses and faffed around until I found on the + terminal there is a double connector that attaches to the battery terminal. This double connector has 4 "tubes" [for want of a better description] of wires running to it and a cover over the terminal itself. Two of the wires had actually come out of their point of the connector. Maybe had not been secured properly with the screw that holds the wires in place.

I undid the screw cleaned and secured the bare wires back in the connector. Drove the car around today and found no problems at all.

I have to presume that the intermittency of the fault was due to these wires being loose and driving over these bumpy roads was the cause of the wires connecting / not connecting. Possibly the load of accelleration / decelleration / braking also making the wires disconnect or at least be loose in the connection at times and not at other times.

I had some work done on the car a couple of months ago apart from the swinging arm bushes and recall the battery needed to be disconnected. The wires must have been pulled at some point but not enough to notice initially until the intermittent fault and finally after parking the car up over a bump at the end of the drive and the wires stayed out of the connector.

Hopefully the problem has been resolved & thanks to all who replied to the topic. There was some good and helpful information in there.

[Sisaketmike]

Update.

The car is now running smoothly again.

The altenator itself is fine. It was a wiring problem. Before I got chance to go to the shop to buy a voltmeter I jumped into the car and had no electrics at all on the dashboard when turning the ignition key.

Checked the fuses and faffed around until I found on the + terminal there is a double connector that attaches to the battery terminal. This double connector has 4 "tubes" [for want of a better description] of wires running to it and a cover over the terminal itself. Two of the wires had actually come out of their point of the connector. Maybe had not been secured properly with the screw that holds the wires in place.

I undid the screw cleaned and secured the bare wires back in the connector. Drove the car around today and found no problems at all.

I have to presume that the intermittency of the fault was due to these wires being loose and driving over these bumpy roads was the cause of the wires connecting / not connecting. Possibly the load of accelleration / decelleration / braking also making the wires disconnect or at least be loose in the connection at times and not at other times.

I had some work done on the car a couple of months ago apart from the swinging arm bushes and recall the battery needed to be disconnected. The wires must have been pulled at some point but not enough to notice initially until the intermittent fault and finally after parking the car up over a bump at the end of the drive and the wires stayed out of the connector.

Hopefully the problem has been resolved & thanks to all who replied to the topic. There was some good and helpful information in there.

Good to know that you've found it. Just fixed my own Mitsu L 200, last night suddenly no more low and high beam...took me an hour to check what was wrong. The relay for the main light where it's being attached had some red ants at the connection. I'm glad that I wasn't driving fast. I guess you saved some money to buy you a beer. Cheers.

[enginerevision]

Good job you found it. I wanna come back to the measure voltage on battery topic. I often have cases where I measure the right charge voltage, but still the dynamo after taken to a specialist seems broken ( diode bridge ) for instance..

So it's never sure..

[Sisaketmike]

Good job you found it. I wanna come back to the measure voltage on battery topic. I often have cases where I measure the right charge voltage, but still the dynamo after taken to a specialist seems broken ( diode bridge ) for instance..

So it's never sure..

What the heck?

You seem to be never sure, that's all. "I often have cases" bla, bla, bla,......

Did anybody tell you that it isn't a dynamo?

A dynamo is producing electricity without input. Why are you writing stories about things you don't even know what they look like inside..and especially how the shit's working.

That makes you to a guy who doesn't know much, but you're trying to help others. So it's never sure what they're writing, like you do.

That's a very big problem in all topics. People who don't know something shouldn't write about it. Full stop.

[WarpSpeed]

Like I said, any one of a hundred issues could be causing the problem based on the information provided, good you found it though and thanx for the update..

Edited May 11, 2010 by WarpSpeed

[enginerevision]

Good job you found it. I wanna come back to the measure voltage on battery topic. I often have cases where I measure the right charge voltage, but still the dynamo after taken to a specialist seems broken ( diode bridge ) for instance..

So it's never sure..

What the heck?

You seem to be never sure, that's all. "I often have cases" bla, bla, bla,......

Did anybody tell you that it isn't a dynamo?

A dynamo is producing electricity without input. Why are you writing stories about things you don't even know what they look like inside..and especially how the shit's working.

That makes you to a guy who doesn't know much, but you're trying to help others. So it's never sure what they're writing, like you do.

That's a very big problem in all topics. People who don't know something shouldn't write about it. Full stop.

You'r a funny guy. Good luck playing mr arrogant.

[stingray]

Good job you found it. I wanna come back to the measure voltage on battery topic. I often have cases where I measure the right charge voltage, but still the dynamo after taken to a specialist seems broken ( diode bridge ) for instance..

So it's never sure..

Basicly it's not a dynamo anymore. They using dynamos 50 years ago. Today the call it alternator. The voltage is always sure.. You can mesure also with Ampere Meter, but there is a easy rule: If there are not enough amere delivered to the battery, than the voltage drops as well. For example: the alternator delivery only 30 Amp (do the the fact it's faulty, broken diode, curquit, etc.), but your car using 50 amp during driving on nights with all the lights, AC, wipers, etc. on. In this case the car using another 20 ampr from the battery, until it's emty. Voltage drops immidently under 12 Volt. Car still running for a while, but not to long.

[centrico]

On the topic of electrics.

Early last year I had an accident. A motorbike ran into the side of the car as I was waiting at a junction. Made a nasty dent in the door and some damage to the door pillar. Took the car to a repair shop. He fixed the door up great. No complaints on the dent removal or the paint job.

Problem was that the battery charge kept going down after that. Sometimes difficult to start the car on a low charged battery. I could not figure out why for a few weeks. H_ll I even bought a new battery presuming the battery life was almost at an end. All was OK for weeks with the new battery. That was until that started to have a reduced charge.

Turned out he had removed the interior light switch inside the door pillar [the one that turns the interior light on when you open the door]. Such a small space to work in and he had tied a bare wire onto the switch. Problem was that live the wire was left too long and not too tight and was earthing out sometimes. As those wires are live with or without the ignition turned on.....

Grrrr. Now I have 2 batteries!!

Again it was poor workmanship but again not easy to detect with no wiring diagram until I downloaded one from the internet.

Joys of motor repairs in Thailand