moose Posted October 11, 2010 Share Posted October 11, 2010 morning all, last week my alternator on my 300tdi died. not opened it up yet but it must have got very hot as there are drips of molten solder round the casing. So i got a new one, it looks like the old one was a 85 amp one but i got a "A127/100 AMP" and fitted it. It seems to be working fine, charging the battery and the dash battery light goes out after the engine is started as normal. But i have no reading on the rev counter? all the terminals are connected correctly, and the rev counter feed is on the "W" spade connector. So any ideas as to what is happening? it there a way to test the "W" feed from the alternator? if i put a multi meter on it what should i be looking for? thanks for any input Paul Quote Link to comment Share on other sites More sharing options...
Puffernutter Posted October 11, 2010 Share Posted October 11, 2010 morning all, last week my alternator on my 300tdi died. not opened it up yet but it must have got very hot as there are drips of molten solder round the casing. So i got a new one, it looks like the old one was a 85 amp one but i got a "A127/100 AMP" and fitted it. It seems to be working fine, charging the battery and the dash battery light goes out after the engine is started as normal. But i have no reading on the rev counter? all the terminals are connected correctly, and the rev counter feed is on the "W" spade connector. So any ideas as to what is happening? it there a way to test the "W" feed from the alternator? if i put a multi meter on it what should i be looking for? thanks for any input Paul It is normally just a series of pulses. I'm not sure if a multimeter will actually show anything. A digital one, most certainly wouldn't as it won't react quick enough. Apart from borrowing another alternator, I'm not sure what else to suggest. Cheers Peter Quote Link to comment Share on other sites More sharing options...
fozsug Posted October 11, 2010 Share Posted October 11, 2010 Try cutting back the wire and putting a new connector on it, worked on mine as the wire was snapped inside the sheathing where it had got too hot Quote Link to comment Share on other sites More sharing options...
moose Posted October 11, 2010 Author Share Posted October 11, 2010 Try cutting back the wire and putting a new connector on it, worked on mine as the wire was snapped inside the sheathing where it had got too hot its an idea as the wire does look a little brittle.. I quess the only way to test if its the alternator would be to steal another one of someone for 5 mins... If turns out not to be the alternator... whats between that wire on the back alternator and the counter? guess no fuses etc.. to check? Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted October 11, 2010 Share Posted October 11, 2010 It's a series of pulses so fast you would need an osciloscope to see them, it is one phase of the 3 phases of AC within the generator and the rev counter sees it as a variable voltage IIRC. Never tried to measure it though so I don't know what I'd expect to see. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.