Need help on '90 200 instrument cluster lights

[Brett Dikeman]

At 11:01 AM -0800 12/22/02, Keith Lawyer wrote:
>My '90 200 has not been charging, and the alt warning
>light is not coming on with the key.  What concerns is
>me is that the light is inconsistent.  Sometimes it
>will come on, sometimes it will not.
>
>The exciter wire looks good

Was there 12v at the terminal?


>1) the alt bulb does not *look* burnt and contacts
>look good.  How can I test the bulb itself?

Multimeter.  Check for continuity.


>  If I
>guess wrong (pos/neg) I blow the bulb, no?

No.  Filaments don't have polarity.

>3) is it ok if I turn on the key with the IC removed
>entirely??

Possibly.  Don't recommend it.


>4)finally, this might mean something to someone: when
>the bulb was not lighting I also got a weird hum from
>the dash/firewall area when I turned the key.

Idle stabilization valve, is my guess.  On the CIS cars, they hum
quite loudly.  Should be easy enough to pinpoint.

Brett
--
----
"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin
http://www.users.cloud9.net/~brett/
http://www.apple.com/switch/