Battery draining on use - alternator Issue?

[TuneR]

A little history, the car has been off the road for a few months as i undersealed, BPU'd the car and then swapped the suspension. I only started her a few days ago and have realised the battery is draining when in use (lights go dim, master/oil low warning lights on dash and then it starts to barely run). I wanted to tax her this month but wont until this issue is fixed. The only electrical work i did was replace the fuel pump with a new Walbro 255 and i reckon that is fine as it works. ATM the car is at a friends as he touchs up the paint a bit but all i can think to check is:

 

• test full battery overnight to see if it holds charge (nothing connected)
  
• fuses
  
• earth connections
  
• belt deflection is good
  
• measure voltage at alternator (only if there is nothing else will i do this)
  

 

I presume there is nothing obvious that i maybe missing?

 

Cheers

[Guest Budz86]

I would guess it's the battery tbh mate, sounds like its not holding charge.

[TuneR]

I would guess it's the battery tbh mate, sounds like its not holding charge.

 

Ya with the cold weather we have had here it very well could be.

[straightsix]

Do you have an alarm fitted? If so, what make?

 

After checking the condition of the battery and charging system you could do with checking for battery drain with an ammeter.

[pedrosixfour]

If the battery is draining with the car running then I'd start with the alternator.

 

For starters do you have a battery light on the dash when you turn on the ignition?

 

The easiest way to check if you alternator is working is to check the current being fed to the battery

 

With the engine running loosen the positive battery terminal, place the positive side of the ammeter on the terminal & then, without delay so the engine doesn't cut out, lift the positive terminal off the battery and clamp the negative side of the ammeter onto the battery pole.

 

If the battery is any way discharged you should see a positive reading on your ammeter if the alternator is working properly, more so if you increase the engine revs.

 

With the ammeter still connected in series and the engine running get someone to turn on some of the car's accessories (lights, wipers, heater, rear window demist etc) if the regulator in the alternator is working properly the reading on the ammeter should dip slightly with each accessory turned on but return to a positive reading straight away.

[TuneR]

Just an update, i measured the alternator and it showed no charge so i took it off and took the front off it. Anyway there were these things that looked broken, im no sure if they are the issue. If someone knows they can say, otherwise im going to drop it to someone to see if they can fix it.

 

 

[TuneR]

Just an update for future reference, that is the rectifier that is blown. Guy fixing it is trying to find one to replace it, hopefully he will as its an expensive part from Toyota!

[straightsix]

Try Cargo

[Guest kolin]

i have faced this type of problem before and i tried to fix it but unfortunately i was unable to fix that issue then i bring this vehicle to car shop they changed the wiring due to damage and also suggest to replace the battery. now it works good..