On board computer display not working

WILLFRANKLIN11

MEMBER
1999 PONTIAC GRAND PRIX
3.8L
6 CYL
2WD
AUTOMATIC
133,000 MILES

My display is not showing up on my interior computer on my dash. I'm not able to see my fuel economy, oil life etc. Replaced the computer with another but didn't solve the issue.
I was wanting to know where to start to troubleshoot. To begin to isolate why the display is not lighting up?
Looking for any information or input please and thank you!

1 Reply

AL514

MECHANIC
4,122 POSTS

Hello, are you able to get to the back of the display? You'll have to check the displays Power and Ground wires with a multimeter. This is the Grand Prix SE model? In the first diagram there are three power wires highlighted in yellow, those should be 12 volts going to the fuses in the second diagram. The two ground wires are highlighted also in the middle of the first diagram. They are labelled to where they go. If you check these and they're all okay, then the display has probably failed.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-use-a-voltmeter

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