Citroen Berling 1998 Battery warning light staying on constantly

[benjmer66]

Hi there, I hope everyone is keeping well,

I have a Citroen Berlingo 1998 1.9d, I have changed the battery and the alternator so they are new but the battery light will not go off, it is permanently on, any suggestions would be really helpful 

kind regards 

Ben M

[cancunia]

Welcome to the forum Ben.

Do you have a multimeter to measure the voltage across the battery terminals when the engine is running?

[benjmer66]

Welcome to the forum Ben.

Do you have a multimeter to measure the voltage across the battery terminals when the engine is running?

Hi there, 

Yes I do, the battery was reading 13/14v output when the engine was running 

Kind regards 

Ben M

[Sol]

Ben, can you check with the meter that there is 12v at the single wire field terminal on the back of the alternator. It should be 12v with ignition on, but not running. Once the engine starts, that terminal will.go to zero because of the alternator now producing electricity. That's what puts the light out. The light bulb is actually the feed for that terminal.

The terminal puts 12v onto the field coils to make the magnetic field required to generate power. Once the field is established and the alternator rotates, the field coil is no longer grounded at the other end so the light goes off.

When charging the battery should ideally read 14.4v - if it's wavering below 14 then it's not working properly. Have you checked the earth strap to the engine from the body, and on to the battery negative? If you can measure a small voltage (any voltage) between battery negative and engine metal then you have a bad or floating earth.

[jj9]

^^^^ what he said 

Put a lump lead from the battery negative to any metal on the engine or better still the body of the alternator, this will rule out the floating earth.


.

[benjmer66]

Hi, I hope your well

I have now checked the earth and seems good, even when I put a jump lead on the battery negative and to the body of the alternator, the battery light does not go out, any other suggestions please. By the way there is also a 12v on the small wire like Zion said when the ignition is on but when I start it the wire is zero like it should.

kindest regards

Ben M

[jj9]

. . . I have changed the battery and the alternator so they are new but the battery light will not go off, it is permanently on . . . 

Is the light on all of the time even when the ignition is off?

Is the light on at full brightness when the engine is off?

Is the light on at full brightness when the engine is running or does it dim down some?

. . . I have now checked the earth and seems good, even when I put a jump lead on the battery negative and to the body of the alternator, the battery light does not go out . . . 

Was the engine running when you done this?


.

[benjmer66]

. . . I have changed the battery and the alternator so they are new but the battery light will not go off, it is permanently on . . . 

Is the light on all of the time even when the ignition is off?

Is the light on at full brightness when the engine is off?

Is the light on at full brightness when the engine is running or does it dim down some?

. . . I have now checked the earth and seems good, even when I put a jump lead on the battery negative and to the body of the alternator, the battery light does not go out . . . 

Was the engine running when you done this?


.

Hi there, 

1. The light is only on when the ignition is on
2. yes on full brightness when ignition on 
3. Also when the engine is running the light is on at full brightness 

The engine was running when I done the procedure with the jump leads

Kind regards 

Ben M

[jj9]

My next step would be to run a thick wire from the positive terminal of the alternator directly to the positive terminal of the battery.

You could possibly do this with a jump lead if you were careful, remember if the jump lead falls off the alternator and touches any metal it will be a dead short!

.

[benjmer66]

My next step would be to run a thick wire from the positive terminal of the alternator directly to the positive terminal of the battery.

You could possibly do this with a jump lead if you were careful, remember if the jump lead falls off the alternator and touches any metal it will be a dead short!

.

Hi there, 

What will this do/ determine 

Kind regards 

Ben M