I have a defender 90 200tdi engine. Recently at high revs there was a squeeling sound (sounded like a belt) this has now stopped however now the battery light is continually on. It is currently starting / running fine but obviously something is wrong ! At high revs the battery light flashes on / off. The battery is only a fee months old. Anyone got any ideas? At the moment I am thinking alternator drive belt?!
Battery light staying on
- Thread starter loopylu
- Start date
This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
SmileySteve
Well-Known Member
- Posts
- 1,423
- Location
- Dumfrieshire
Alternator failing, the squealing may of been fan belt slip but can also be bearing failure in the alternator.
Have seen light come on at high revs on worn out alternators before as the brushes can lose contact with the armature.
If you have a volt meter you can measure at the battery and check volts while ticking over and revving up, though tbh I reckon alternator is on its way out.
Have seen light come on at high revs on worn out alternators before as the brushes can lose contact with the armature.
If you have a volt meter you can measure at the battery and check volts while ticking over and revving up, though tbh I reckon alternator is on its way out.
blue beasty
Leaks an prone to bits dropping off
- Posts
- 64,220
- Location
- Gloucestercotshirewolds
+1 loose belt usually squeals at low revs.
200tdi should have a seperate belt for the alternator from the power steering belt
Also halfords do free battery and alternator tests
Also halfords do free battery and alternator tests
Last edited:
sp00k
Well-Known Member
- Posts
- 1,530
- Location
- Washington, County Durham, UK
All electricals in the defender need power from the alternator. Without the alternator, these will draw energy from the battery until it's depleted.
Even in daylight with all accessories off, the fuel solenoid and brake lights will draw power. This would not be an issue for a charged, strong battery for short periods.
Starting the engine and running lights will quickly deplete the battery. If it's discharged too much or for too long, the battery life will be conpromised.
Even in daylight with all accessories off, the fuel solenoid and brake lights will draw power. This would not be an issue for a charged, strong battery for short periods.
Starting the engine and running lights will quickly deplete the battery. If it's discharged too much or for too long, the battery life will be conpromised.
You should be fine for a 90 mile day journey without rain, fuel solenoid is minimal consumption, if we assume that is two hours then a good battery will last the distance as long as you:
Start it the minimum of times - this is where power gets used.
Lights off
Radio off
Heater fan off
Window demist off
Wipers off.
Indicators only when needed - some never bother with them at all !!!
Don't hold it on the brakes at junctions - leaves brake lights on.
Start it the minimum of times - this is where power gets used.
Lights off
Radio off
Heater fan off
Window demist off
Wipers off.
Indicators only when needed - some never bother with them at all !!!
Don't hold it on the brakes at junctions - leaves brake lights on.
I just had this issue with my 300tdi (minus the squealing). Battery light was on continually and would only disappear for a couple seconds at a time at high rpms.
Voltmeter across the battery showed just 12.8V even with my foot on the peddle. (Undercharging).
Belt was in good condition and tension was correct. Took alternator out and replaced(not all at once) regulator, diode plate, slip ring and the bearing in the end cover. Now at idle I measure about 13.9 -14 V which indicates the alternator is once again charging the battery.
My advice: if you've decided not to buy a new one and are having the alternator rebuilt try to change as much of the components if not all at once. If you're like me and only change one at a time you just might end up burning lots of time. I ended up removing the alternator and changing parts about 3 times until I resolved this issue.
But it was a great learning experience. All the best.
Voltmeter across the battery showed just 12.8V even with my foot on the peddle. (Undercharging).
Belt was in good condition and tension was correct. Took alternator out and replaced(not all at once) regulator, diode plate, slip ring and the bearing in the end cover. Now at idle I measure about 13.9 -14 V which indicates the alternator is once again charging the battery.
My advice: if you've decided not to buy a new one and are having the alternator rebuilt try to change as much of the components if not all at once. If you're like me and only change one at a time you just might end up burning lots of time. I ended up removing the alternator and changing parts about 3 times until I resolved this issue.
But it was a great learning experience. All the best.
Oscar Romeo
New Member
- Posts
- 157
Check across your battery terminals with a digital volt meter, with the engine running you should be looking for some thing around 14 volts anything below 13.6 is below the gaseous phase of the charge cycle and your battery wont charge.
If you have 14volts and the light is still on you have a problem with the warning side of your system.
If you don't have 14volts then you have a charge fault, your battery will provide power till it flattens as it isn't being charged and your truck will stop.
this could be as simple as a loose connection. changing batteries and alternators
Should be after you have checked everything else unless you have deep pockets.
Regards
Lee
If you have 14volts and the light is still on you have a problem with the warning side of your system.
If you don't have 14volts then you have a charge fault, your battery will provide power till it flattens as it isn't being charged and your truck will stop.
this could be as simple as a loose connection. changing batteries and alternators
Should be after you have checked everything else unless you have deep pockets.
Regards
Lee
