Ignition Light

[290Gee]

Hello all

I have a charging problem with my Merc G Wagen. When I start my truck the ignition light goes out. But in the dark it gives off a very dim glow. I have measured the voltage across my battery with the truck running and it shows a consistent 12.7-8 volts. I have changed the regulator only to find the voltage to be the same, but the light is still glowing dimly.

The battery is a new Odyssey starting/deep cycle battery.

Any ideas please

 

[television]

Well the dim lamp normally means a diode down. As you have replaced the reg pack this must be an exciter fault, but would appear to be in order as the lamp is working. One leg is clearly down and the voltage is too low.

I think that you will have to give the alternator to a Bosch service center to test it on the test rig.

Malcolm

 

[290Gee]

Many thanks for this. Is the voltage correct at the battery or should it be higher?

 

[television]

Many thanks for this. Is the voltage correct at the battery or should it be higher?

You are not charging, the alternator is giving something out, but low.

The running voltage should be 13.8-14 volt, that leaves 2 volts to charge the battery. When the light is on dim,it means a fault on one of the 3 + diodes.

If the new one is the same as the old, then one of the slip rings in the alternator could be worn down so that the brush no longer makes contact.

Some firms rebuild, I would look in yellow pages for a Bosch service center.

Malcolm