Pilot

Member
300tdi
When the car is started everything is fine. After about 5 minutes running, the tachometer stops working and the ignition light comes on.
Anyone got an idea whats what?
 
I don’t know the D1 but. Does the Rev counter signal come from the alternator, which could be a reason your light comes on. Duff alternator?
@discool ?

J
 
The connection on the alternator often becomes loose. Tt is just an ordinary push on connector, find it and check it is tight before going any further.
 
just because it shiny and new does not mean it's working ( could be a Chinese interment camp rebelling against the lose of body organs )
 
The connection on the alternator often becomes loose. Tt is just an ordinary push on connector, find it and check it is tight before going any further.
Yes the connection is good. Both cables, the copper was quite black, so I cut the back and rewired the. Im sure its not a connection issue. I cant see why the tachometer and the ignition light should be effected together.
 
Yes the connection is good. Both cables, the copper was quite black, so I cut the back and rewired the. Im sure its not a connection issue. I cant see why the tachometer and the ignition light should be effected together.
When similar happened to me the little wire that leads to the tach had come right off, nothing to do with the thick wires going to the batt and elsewhere. I found it, tweaked up the connection, slid it back on and my tach started reading again.
I'd take a pic of the connections if I was in the right country.
This is the only thing I could find quickly for you re the connections
 
Yes the connection is good. Both cables, the copper was quite black, so I cut the back and rewired the. Im sure its not a connection issue. I cant see why the tachometer and the ignition light should be effected together.
Maybe because they are both managed by the alternator and at a point the signals are going through the same connector... though as long as you are so cryptic and you dont reveal important details i asked(+ your disco's m. year) i can't help you so good luck
 
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300tdi
When the car is started everything is fine. After about 5 minutes running, the tachometer stops working and the ignition light comes on.
Anyone got an idea whats what?
The ignition warning light and rev counter are two different circuits, turning the switch to position 2 the lamp should illuminate and the spinning alternator turns it off, the alternator supplies a pulse signal for the rev counter, now its possible that you have a faulty alternator, the new one was a exact match to the old, was it brand new or maybe an iffy refurbished ?

Your VIN is needed to get the correct replacement , although all 300 series petrol or diesel work on the same principle there some slight variation between 1995 96 97 and 1998MY with fitment and power output but they will all charge your battery.
 
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The ignition warning light and rev counter are two different circuits, turning the switch to position 2 the lamp should illuminate and the spinning alternator turns it off, the alternator supplies a pulse signal for the rev counter, now its possible that you have a faulty alternator, the new one was a exact match to the old, was it brand new or maybe an iffy refurbished ?

Your VIN is needed to get the correct replacement , although all 300 series petrol or diesel work on the same principle there some slight variation between 1995 96 97 and 1998MY with fitment and power output but they will all charge your battery.
Turns out you are spot on. The brand new Hella alternator is not out putting any voltage. Ill contact the supplier after the weekend holiday and arrange a replacement.
Thanks to every one for their input.
 
for the alternator to produce current / voltage it needs a supply from the battery to start the process

so it's one of the wires connected to the alternator
 

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