850 warning lights remain dim

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daniel swetschinski

in my wife's 850 some of the warning lights on the dashboard ["low
washer fluid"," bulb failure", "low fuel", "generator not charging",
"low coolant", "brake", and "park brake" lights] remain dimly lit
after starting the car and while driving around. when they really
indicate a warning--as when I step on the brakes and the bulb failure
lights up because one of my brake lights is really busted--the warning
light brightens.

I have worked on the electrical system of my 240 [with a lot of
patience, by following the lines in the wiring diagram] but have no
experience doing any electrical work on the 850. it looks a whole lot
more complicated.

does anyone, perhaps, have a ready or more or less plausible solution
for this problem? is there a relay that needs to be checked and/or
replaced?

thanks, Daniel
 
in my wife's 850 some of the warning lights on the dashboard ["low
washer fluid"," bulb failure", "low fuel", "generator not charging",
"low coolant", "brake", and "park brake" lights] remain dimly lit
after starting the car and while driving around.

does anyone, perhaps, have a ready or more or less plausible solution
for this problem?

You likely have a bad ground for the instrument panel.
 
daniel said:
in my wife's 850 some of the warning lights on the dashboard ["low
washer fluid"," bulb failure", "low fuel", "generator not charging",
"low coolant", "brake", and "park brake" lights] remain dimly lit
after starting the car and while driving around. when they really
indicate a warning--as when I step on the brakes and the bulb failure
lights up because one of my brake lights is really busted--the warning
light brightens.

I have worked on the electrical system of my 240 [with a lot of
patience, by following the lines in the wiring diagram] but have no
experience doing any electrical work on the 850. it looks a whole lot
more complicated.

does anyone, perhaps, have a ready or more or less plausible solution
for this problem? is there a relay that needs to be checked and/or
replaced?

thanks, Daniel

This happens when one of the 3 phases in the alternator is shorted to
ground. Putting a scope on the alternator output will confirm if this
is a problem, or measure battery voltage with the engine at or above
2000 rpm and the lights, heater fan, rear defogger etc. on.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)
 
Thanks for the succinct answers. I suppose this is what happens when
you venture beyond a certain, relatively low level of expertise. I'm
not sure what the info means that you gave me.

Presently the car's battery is dead and needs to be recharged. With
"one of the 3 phases in the alternator shorted to ground" do I just
replace the alternator (which is only slightly more than 2 yrs old) or
do I have to do something else? I have replaced this alternator before
and could probably find brushes if those needed to be replaced, but I
hate to do all that work only to find out that in my eagerness to hide
my stupidity, I overlooked the answer most obvious to anyone who
really knows how electrical systems work. I hate to bother you again,
but want to be practical.

Thanks again, Daniel

daniel said:
in my wife's 850 some of the warning lights on the dashboard ["low
washer fluid"," bulb failure", "low fuel", "generator not charging",
"low coolant", "brake", and "park brake" lights] remain dimly lit
after starting the car and while driving around. when they really
indicate a warning--as when I step on the brakes and the bulb failure
lights up because one of my brake lights is really busted--the warning
light brightens.

I have worked on the electrical system of my 240 [with a lot of
patience, by following the lines in the wiring diagram] but have no
experience doing any electrical work on the 850. it looks a whole lot
more complicated.

does anyone, perhaps, have a ready or more or less plausible solution
for this problem? is there a relay that needs to be checked and/or
replaced?

thanks, Daniel

This happens when one of the 3 phases in the alternator is shorted to
ground. Putting a scope on the alternator output will confirm if this
is a problem, or measure battery voltage with the engine at or above
2000 rpm and the lights, heater fan, rear defogger etc. on.
 
daniel swetschinski said:
Thanks for the succinct answers. I suppose this is what happens when
you venture beyond a certain, relatively low level of expertise. I'm
not sure what the info means that you gave me.

Presently the car's battery is dead and needs to be recharged. With
"one of the 3 phases in the alternator shorted to ground" do I just
replace the alternator (which is only slightly more than 2 yrs old) or
do I have to do something else? I have replaced this alternator before
and could probably find brushes if those needed to be replaced, but I
hate to do all that work only to find out that in my eagerness to hide
my stupidity, I overlooked the answer most obvious to anyone who
really knows how electrical systems work. I hate to bother you again,
but want to be practical.


If that's the problem, then yes, replace the alternator. You can have it
tested at any autoparts store though and I would do that before replacing it
blindly.
 
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