Diagnosing faults help

Gilly

Gilly

Gilly

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Before we get going I might get the answer half way through as I'm waiting for a garage to call me back.

Still got the Clio Cup outside, though my daily drive has become a Passat. Unfortunately longer than I realised has gone by without my driving the Clio and it's having power issues.

The power from the battery reports 11.7 volts, and with my rudimentary knowledge I believe that's about .3 off exact, and is fairly ideal. I can jump start it off the Passat and it starts pretty much immediately. As well as it ever did before.

The problem comes when I turn the Passat and the Clio off, disconnect the jump cables, and return to the Clio. I have once heard the starter motor try to turn over, but mostly I get a very loud clicking noise (much louder than the relay click I also hear) and no starter motor.

Any ideas as to what is causing the problem? Obviously even though I can get the engine running (and even with the Passat off it continues to run fine on its own for 30 mins +) I can't take it for a drive.
 
Isn't it current you need to the starter motor?

I have no idea how you'd measure that, really, because I'm stupid. But it sounds like it just can't supply enough current to turn the starter motor...

May just need a good run out (why can't you take it for a drive) to charge it up a bit?

/here endeth the ignorance.
 
Apparently you can't disconnect the jumper cables whilst the car is running (it is possible to damage the electronics on both cars if you do) and I can't get it to start without it being connected to the donor car.
 
Really? OK, it's a randomer on a questions website, but this seems to state it is higher than normal?
 
Just sounds like a simple flat battery to me. The clicking is the starter solenoid. Get a battery charger and put some juice back in it. If it doesn't hold charge very well then you may need a new battery.

I had this problem a few months ago, mostly because I was doing mainly short trips in very cold weather with lights on, heater, heated rear windscreen etc and the alternator didn't have time to charge the battery up. Recharged it and its been fine ever since.
 
11.7 is too low but as said the Amps matter

Had to look atmy parents acr and it was showing over 11 volts butonly 20 amps

take the battey off take it to battery place and they will test properly but lamost certainly you eed a new one

i decent battery will read about 12.8 V idle and 14V with engine tunning
 
Fusion said:
Just sounds like a simple flat battery to me. The clicking is the starter solenoid. Get a battery charger and put some juice back in it. If it doesn't hold charge very well then you may need a new battery.
Click to expand...

There's juice going into it from the engine running and the donor car, no?

Rotty said:
11.7 is too low but as said the Amps matter

Had to look atmy parents acr and it was showing over 11 volts butonly 20 amps

take the battey off take it to battery place and they will test properly but lamost certainly you eed a new one

i decent battery will read about 12.8 V idle and 14V with engine tunning
Click to expand...

Bit early to be drinking mate :D
 
Battery makers are liars, you will never see a 12v battery they are all around 13v (6 cells of ~2.2v each), 11.7 is nigh on flat.

The clicking noise your hearing is the starter motor solenoid, it has enough power to engage the solenoid which closes the loop to the main motor, the motor pulls what amps the battery has which doesnt leave enough for the solenoid and this opens the loop. With the main motor no longer pulling amps there is enough power for the solenoid to move..... and you are in a circle of the solenoid bouncing in and out.
 
Ah, now that makes sense. Thanks for explaining that :)

So we're sure on it being the battery? I'll take it with me when I go buy one anyway, and get them to check it. Prices seem to vary wildly, what should I be paying?
 
Battery is dead by the sound of it. A proper overnight re charge might spark it back into life.

EDIT- slow reply as I got caught on the phone.

When buying batteries I always suggest that people go with a name that they have heard of and then narrow it down by whichever has the best warranty without having to pay a huge premium.
 
Battery warranties arent worth a great deal anyway, most say '3 year cover'. but in reality you are only covered for a dead cell occurrence anything else is just wear and tear and will be ignored.

As a whole we usually fit bosch blue tops, never had any issues. A bit more pricey at around £70 though.
 
Deeply discharging a battery will kill it eventually. Unless it's recent, I wouldn't even bother trying to recharge it. Bin it and buy another.
 
May be worth giving it a charge over night, if you have access to a battery charger.

And are you not supposed to take off jump leads when engines are running? I've done it plenty of times, so long as both the positive/negative cables are taken off at the same time on each car.
 
I have done that many a time (disconnected the leads with the engine running).

IMHO, paying circa £100 for a brand new battery is a huge waste of money when most scrapyards have a shipping container FULL of perfectly working batteries for a tenner each. Certainly at both of my local yards they will let you choose the battery you want and then actively test the battery in front of your eyes before you take it away. If it turns out that it doesn't work or whatever then they will just swap it for you.

Even if they don't last as long as a brand new one, you'd have a job to get through 10 in the life of a brand new one!
 
Sounds like battery; Mainly due to the cold and the fact that I do short trips every where, drained my battery last night.

The loud clicking is correct that it's the solenoid ticking over.

Two choices really, run it for an extended period of charge, both jumped then taken out for a deent blast (minimum 30 minutes). Or get a new battery.
 
DRZ said:
I have done that many a time (disconnected the leads with the engine running).

IMHO, paying circa £100 for a brand new battery is a huge waste of money when most scrapyards have a shipping container FULL of perfectly working batteries for a tenner each. Certainly at both of my local yards they will let you choose the battery you want and then actively test the battery in front of your eyes before you take it away. If it turns out that it doesn't work or whatever then they will just swap it for you.

Even if they don't last as long as a brand new one, you'd have a job to get through 10 in the life of a brand new one!
Click to expand...

This is what I usually do, except they are £5 at my local.

You can also pick them up from the battery disposal point at your local tip (well you can here) but there will be no testing unless you bring your own.
 
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