rmendoza

Just returned from Kuwait supporting our troops. Bought a '90 Corvette convertible on ebay. Seems to be in pretty good shape with a few things that I will need to fix.

This is an electrical problem I guess. When idling with no lights on, the speedometer background flickers as does the radio and electronic heating and air conditioner indicators and the voltmeter.

The flicker can also be seen at idle in the headlights. Of course when driving or reving higher than idle flicker can't be seen.

Also when turning the engine off, the speedometer background light remains lit for about 2 seconds, is this normal?

Any help would be appreciated.
thx
rick

trulytex

Let me start out by saying God Bless you & commend you for your service to our country. Thanks You. And congrats on you Corvette adoption! I purchased my first Corvette 2 months ago, a 1990 convertible and I love it. My speedo background lights also pulse as you have described. I don't know if it is normal, but it's not uncommon. I don't recall if my speedo background light stays lit after shut-down, but I don't think it does. The guys & ladies on this forum can definitely help with your problems with a smattering of well intentioned constructive criticisms.

jfb

With engine idling, lights flickering, unplug the connector on the alternator. If the flickering stops, you have an oscillating voltage regulator in the alternator. An auto electrical shop can replace the voltage regulator, or you can do it yourself, or you can replace the alternator. If you have an alternator with a lifetime guarantee, just replace it.

C4DC

I know that many do it, my 96 included. Thank you for your service to our country!

runner140*

Start checking your grounds starting with the main ground around your battery and work out from there. Sounds like a bad ground problem to me.

RRT vette

with jfb.

Fuzzy Dice

The dash lights on my 93 began flickering and I started calling my car "disco vette"...lol...turns out it was the voltage regulator so I took this opportunity to upgrade to a 140 amp alternator...

rmendoza

On the Flickering lights, the following suggestions are what I got:
"With engine idling, lights flickering, unplug the connector on the alternator. If the flickering stops, you have an oscillating voltage regulator in the alternator. An auto electrical shop can replace the voltage regulator, or you can do it yourself, or you can replace the alternator. If you have an alternator with a lifetime guarantee, just replace it."

Finally, how did you load the image that is under your user name? I want to load a picture of my '90 corvette there but can't find out where you do that.

Thanks again
rick mendoza

I got this reply from several owners with varying years of corvettes, so it must be a pretty common problem. Thought I'd share that with you for your future reference.

Thanks for the comment on my service. I actually retired after 37 yrs of Government Civil Service, having worked on A/C, ICBMs, NASA and DOD Spaced Systems. For six month after retirement I enjoyed the '86 Corvette that I had at the time and took many road trips. Finally board and with things getting hot in the middle east, I wanted to contribute so I took a job in Kuwait May of "03. We provided all the support to the Army going in and out of Iraq. I shared 3 Thanksgivings and 2 Christmas Day meals with the greatest resource this country has. Eventhough, I missed my family, it was truly the most rewarding time of my life.

rmendoza

Thank you Sir! It doesn't seem to be a problem but is a little irratating. Of course it has a purpose so I need to get it fixed.

thx again
rick mendoza

rmendoza

On the Flickering lights, the following suggestions are what I got:
"With engine idling, lights flickering, unplug the connector on the alternator. If the flickering stops, you have an oscillating voltage regulator in the alternator. An auto electrical shop can replace the voltage regulator, or you can do it yourself, or you can replace the alternator. If you have an alternator with a lifetime guarantee, just replace it."

Thanks for your response, thought I'd share with you.

thx
rick mendoza

rmendoza

On the Flickering lights, the following suggestions are what I got:
"With engine idling, lights flickering, unplug the connector on the alternator. If the flickering stops, you have an oscillating voltage regulator in the alternator. An auto electrical shop can replace the voltage regulator, or you can do it yourself, or you can replace the alternator. If you have an alternator with a lifetime guarantee, just replace it."

Thanks for your response, I'll also check the ground.

thx
rick mendoza

rmendoza

Thanks for your response. Based an the responses from a number of owners of various year corvettes, seems to be a common occurrence. One even used the opportunity to upgrade to a 140 amp alternator, is that correct and what is your opinion on that?

thx again
rick mendoza

rmendoza

Thanks, based on responses I've received, that seems to be a common occurence.

So is the upgrade to a 140 amp alternator working out? and do you recommend it?

thx again
rick mendoza

patsfan

Thanks for your service to this great country we live in

I've noticed it with my 1991 and it has bothered / annoyed me . I haven't been able to trouble shoot it / research it yet do to more important /drivability issues holding priority over it .
please post when you found out what it was that was causing it

patsFan

Sam Lam

Rick: My 89 had a problem with the instrument lights going dim and then they would go bright. My problem was a corroded (dirty) main bulkhead connector. This main connector is located just behind the battery and can easily be cleaned. I would recommend doing this work before you spend any of that hard earned $$$ protecting our country. If you need more info on this, send me an email to samlam@charter.net.