HI,
I have a bit of a problem with the wife's Stilo 150Multijet. 2007 & only 75000 miles - we've had it since 2010 & it's been great - couple of rear discs & an exhaust hanger or two & every MOT a pass. No Check Engine lights since a mouse chewed a temp sensor connector a few years back,set of glowplugs & I did the cambelt for the second time last October.
Anyway... couple of nights ago the Charge warning lamp came on & power steering was lost. Sure enough, there was only 11.8v showing across the battery with the engine running. Disconnected & put the battery on charge overnight. Following morning the same – alternator not charging.
I looked through the threads on the forum https://www.fiatforum.com/threads/alternator-charging-light.488929/
&
https://www.fiatforum.com/threads/alterator-escape-route.462792/#post-4359663
& did some further checks:-
Battery terminals are clean, battery is a Varta new 14 months ago.
Car starts fine, then shows Charge Warning light after say 20 seconds running, or if you switch on a load (headlights e.g.) Power steering is then not working.
Voltage only 11.9-12 at battery engine running.
All fuses fine & all fusebox terminals like new.
Ditto all terminals on the infamous D4 connector which is clean & dry.
I’ve put a smear of contact grease on all connections in fusebox.
D4 terminal to alternator wire (the excitation connection) is fine, but cleaned ends anyway.
Alternator terminals are like new (amazing after 15 years & lots of puddles up our lane).
Before I replace the alternator (not a job I am looking forward to), the only untoward thing I have found is that the excitation wire on the alternator is at only 9.5v with ignition on. Opening the D4 connector yet again I found that the upstream feed is only showing 9.5v too, so the connector is passing all the voltage it receives to the alternator.
I have the following queries:-
Is this sufficient to excite the alternator or should it be 12v?
Does this feed ( a very thin blue wire) come from the body computer terminal 19 as stated in one of the posts?
Where is the body computer in that case?
If I go back to the “good old days” & remove the exciter wire & apply 12v to the alternator to see if it then starts charging, am I likely to cook something?
It’s a b*gger when the thing is so inaccessible you can’t just remove it from the car to test, with no risk to anything else...
I have a bit of a problem with the wife's Stilo 150Multijet. 2007 & only 75000 miles - we've had it since 2010 & it's been great - couple of rear discs & an exhaust hanger or two & every MOT a pass. No Check Engine lights since a mouse chewed a temp sensor connector a few years back,set of glowplugs & I did the cambelt for the second time last October.
Anyway... couple of nights ago the Charge warning lamp came on & power steering was lost. Sure enough, there was only 11.8v showing across the battery with the engine running. Disconnected & put the battery on charge overnight. Following morning the same – alternator not charging.
I looked through the threads on the forum https://www.fiatforum.com/threads/alternator-charging-light.488929/
&
https://www.fiatforum.com/threads/alterator-escape-route.462792/#post-4359663
& did some further checks:-
Battery terminals are clean, battery is a Varta new 14 months ago.
Car starts fine, then shows Charge Warning light after say 20 seconds running, or if you switch on a load (headlights e.g.) Power steering is then not working.
Voltage only 11.9-12 at battery engine running.
All fuses fine & all fusebox terminals like new.
Ditto all terminals on the infamous D4 connector which is clean & dry.
I’ve put a smear of contact grease on all connections in fusebox.
D4 terminal to alternator wire (the excitation connection) is fine, but cleaned ends anyway.
Alternator terminals are like new (amazing after 15 years & lots of puddles up our lane).
Before I replace the alternator (not a job I am looking forward to), the only untoward thing I have found is that the excitation wire on the alternator is at only 9.5v with ignition on. Opening the D4 connector yet again I found that the upstream feed is only showing 9.5v too, so the connector is passing all the voltage it receives to the alternator.
I have the following queries:-
Is this sufficient to excite the alternator or should it be 12v?
Does this feed ( a very thin blue wire) come from the body computer terminal 19 as stated in one of the posts?
Where is the body computer in that case?
If I go back to the “good old days” & remove the exciter wire & apply 12v to the alternator to see if it then starts charging, am I likely to cook something?
It’s a b*gger when the thing is so inaccessible you can’t just remove it from the car to test, with no risk to anything else...