Dim Dash LCD Speed Display - ZR-1 Net Registry Forums

SteelBlueZR1 · 11-01-2011

Has anyone else had an issue with the LCD Speed/Gas gauge display being dim and gray vs. showing dark black digits? My car has very low mileage, and i wonder if there is corrosion on the pins on the back of instruments vs. grounds making bad contact. I notice that the LCD backlight dims when I press on the brake pedal at idle.

Where are the grounds for the instruments located and how do you access them to clean them? I read about someone who just cleaned the pins on the back of the instrument pane with alcohol and the connector and the display is now dark uniform black. Any sage input or solutions before I proceed to remove the instruments is appreciated?

Kb7tif · 11-02-2011

The lcd portion wears out. I have 3 exact same replacements and All have a different brightness.

SteelBlueZR1 · 11-03-2011

Thanks for the feedback on this issue. In case I clean the contacts and grounds (does anyone know where the instrument grounds are exactly located?) and I still have very light LCD speedo numbers, are any of your LCD panels available for sale?

ZR1@gmx.com · 11-04-2011

My display has started dimming as I drive it... It slowly flashes from bright to dim, I hope to learn how to fix this too!

RICHARD TILL · 11-05-2011

Me 2.

captcorvette · 11-05-2011

Add me to the list. This same issue happens on my '90 ZR1 and my '90 & '91 roadsters.

SteelBlueZR1 · 03-13-2012

So, I finally cleaned any corrosion on the pins on the back of the instrument panel and the connector with alcohol and steel wool, but the digital speedometer display is still dim. Has anyone else come up with a solution for the dim speedometer LCD display? I still plan to clean the ground at the driver's side foot well/speaker cover.

Kb7tif · 03-13-2012

The display gets weak, I have 3 over here and have 3 different brightness's
from almost unreadable to normal. All from the same car.

See if you can swap out a known good unit.
Ive been thru all of this- its rarely grounds
or this kind of thing.
All of the functions ( digital segments ) are controlled by the CCM and Pcm together. As far as anything but the backlighting .That rarely goes out.
Try a known good unit.

mike100 · 03-14-2012

Is it the backlight? try turning on your headlamps and adjusting the dimmer lever to maximum brightness.

seems like my 95 LT1 car dimmer function used to work all the time regardless of headlamp function, but the early ones need the lamps on for the dimmer to adjust. they even made the gauge ink white instead of dark yellow on the 94-up cars...obviously these were a little challenging to see even new.

Paul Workman · 03-14-2012

If stepping on the brake causes change in the luminance, "grounding" is the first thing that comes to mind. The FSM should help. But, in the mean time, the two circuit ground reference points are on the back of the block at the edge of the bell housing, each right/left bolt is about 6 inches either side of top-center of the periphery. There are 4 lugs on one bolt, and 5 lugs on the other.

As for the connectors on the instrument cluster, there are two; the main one at the corner of the board, and the other is at the top, which serves the LCD pannel. Both connectors can be and should be replaced, if there is any sign of "frosting" (whiteish oxidation) on the pins. (I ran across those connectors a few times when I was searching for parts for the board. I'll see if I can dig them up again.)

P.

11-01-2011	#1
SteelBlueZR1 Join Date: Aug 2011 Location: Evergreen, Co. Posts: 344	Dim Dash LCD Speed Display Has anyone else had an issue with the LCD Speed/Gas gauge display being dim and gray vs. showing dark black digits? My car has very low mileage, and i wonder if there is corrosion on the pins on the back of instruments vs. grounds making bad contact. I notice that the LCD backlight dims when I press on the brake pedal at idle. Where are the grounds for the instruments located and how do you access them to clean them? I read about someone who just cleaned the pins on the back of the instrument pane with alcohol and the connector and the display is now dark uniform black. Any sage input or solutions before I proceed to remove the instruments is appreciated?

11-02-2011	#2
Kb7tif Join Date: May 2009 Location: S Nevada Posts: 351	Re: Dim Dash LCD Speed Display The lcd portion wears out. I have 3 exact same replacements and All have a different brightness.

11-03-2011	#3
SteelBlueZR1 Join Date: Aug 2011 Location: Evergreen, Co. Posts: 344	Re: Dim Dash LCD Speed Display Thanks for the feedback on this issue. In case I clean the contacts and grounds (does anyone know where the instrument grounds are exactly located?) and I still have very light LCD speedo numbers, are any of your LCD panels available for sale?

11-04-2011	#4
ZR1@gmx.com Join Date: Oct 2010 Location: Sedalia, MO Posts: 150	Re: Dim Dash LCD Speed Display My display has started dimming as I drive it... It slowly flashes from bright to dim, I hope to learn how to fix this too!

11-05-2011	#5
RICHARD TILL Join Date: Aug 2005 Location: Iuka, Mississippi 38852 Posts: 756	Re: Dim Dash LCD Speed Display Me 2.

11-05-2011	#6
captcorvette Join Date: Jan 2011 Location: Dubai, United Arab Emirates Posts: 449	Re: Dim Dash LCD Speed Display Add me to the list. This same issue happens on my '90 ZR1 and my '90 & '91 roadsters.

03-13-2012	#7
SteelBlueZR1 Join Date: Aug 2011 Location: Evergreen, Co. Posts: 344	Re: Dim Dash LCD Speed Display So, I finally cleaned any corrosion on the pins on the back of the instrument panel and the connector with alcohol and steel wool, but the digital speedometer display is still dim. Has anyone else come up with a solution for the dim speedometer LCD display? I still plan to clean the ground at the driver's side foot well/speaker cover.

03-14-2012	#9
mike100 Join Date: Feb 2011 Location: San Marcos CA Posts: 1,786	Re: Dim Dash LCD Speed Display Is it the backlight? try turning on your headlamps and adjusting the dimmer lever to maximum brightness. seems like my 95 LT1 car dimmer function used to work all the time regardless of headlamp function, but the early ones need the lamps on for the dimmer to adjust. they even made the gauge ink white instead of dark yellow on the 94-up cars...obviously these were a little challenging to see even new.

03-14-2012	#10
Paul Workman Join Date: Nov 2007 Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri Posts: 6,466	Re: Dim Dash LCD Speed Display If stepping on the brake causes change in the luminance, "grounding" is the first thing that comes to mind. The FSM should help. But, in the mean time, the two circuit ground reference points are on the back of the block at the edge of the bell housing, each right/left bolt is about 6 inches either side of top-center of the periphery. There are 4 lugs on one bolt, and 5 lugs on the other. As for the connectors on the instrument cluster, there are two; the main one at the corner of the board, and the other is at the top, which serves the LCD pannel. Both connectors can be and should be replaced, if there is any sign of "frosting" (whiteish oxidation) on the pins. (I ran across those connectors a few times when I was searching for parts for the board. I'll see if I can dig them up again.) P.