Hi all, a bit of a cheeky post as this is a general enquiry not MB specific but I’ve run out of places to ask for help.
I have a diesel engine with a tacho which I understand works by sensing pulses from the alternator. Twice in the last month the tacho has gone off the scale on start-up and stayed there. It’s reading full scale deflection even when the engine is only idling.
There is also an hour-meter LCD display in the tacho and that flickers on and off without fully showing any numbers.
Finally, once started-up sometimes the alternator output can be low (ca11.8 ~ 12.4V) until the engine is gently rev’d.
Any suggestions of where to start diagnosing the problem? There is no CAN bus so I thought checking the output voltage of the “W” wire from the alternator first, even if I cannot measure the frequency.
Thanks for reading.
I have a diesel engine with a tacho which I understand works by sensing pulses from the alternator. Twice in the last month the tacho has gone off the scale on start-up and stayed there. It’s reading full scale deflection even when the engine is only idling.
There is also an hour-meter LCD display in the tacho and that flickers on and off without fully showing any numbers.
Finally, once started-up sometimes the alternator output can be low (ca11.8 ~ 12.4V) until the engine is gently rev’d.
Any suggestions of where to start diagnosing the problem? There is no CAN bus so I thought checking the output voltage of the “W” wire from the alternator first, even if I cannot measure the frequency.
Thanks for reading.
