No parking or running lights
Thread Starter
Cruising
Joined: Oct 2007
Posts: 11
Likes: 0
No parking or running lights
Have a 99 C5 Convert. and when we put the lights on, all we have are headlights. No parking, running or dash lights. But if we turn on the Twilight it all works till we shut the vette off. No blown fuses, relays seem OK. All grounds seem clean and tight. Any suggestions.
Tech Contributor
Joined: Dec 2003
Posts: 19,384
Likes: 87
From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
If the automatics work you know the lighting system is sound. If the fuses are all good I'd suspect the switches which often fail.
Could be the multi function switch on the column or the hazard warning switch. To try to tie it down, start with the hazard switch and recycle it firmly a few times and see if the lights come back. If that doesn't work do the same on the manual headlight switch on the column. Also try spraying some electronics cleaner into the switch to clean up the contacts.
If either solution works you've identified the problem. If it keeps reocurring it may need a switch change.
Any lighting related DTCs?
Could be the multi function switch on the column or the hazard warning switch. To try to tie it down, start with the hazard switch and recycle it firmly a few times and see if the lights come back. If that doesn't work do the same on the manual headlight switch on the column. Also try spraying some electronics cleaner into the switch to clean up the contacts.
If either solution works you've identified the problem. If it keeps reocurring it may need a switch change.
Any lighting related DTCs?
Burning Brakes
Joined: Apr 2007
Posts: 966
Likes: 9
From: Phoenix AZ
If the automatics work you know the lighting system is sound. If the fuses are all good I'd suspect the switches which often fail.
Could be the multi function switch on the column or the hazard warning switch. To try to tie it down, start with the hazard switch and recycle it firmly a few times and see if the lights come back. If that doesn't work do the same on the manual headlight switch on the column. Also try spraying some electronics cleaner into the switch to clean up the contacts.
If either solution works you've identified the problem. If it keeps reocurring it may need a switch change.
Any lighting related DTCs?
Could be the multi function switch on the column or the hazard warning switch. To try to tie it down, start with the hazard switch and recycle it firmly a few times and see if the lights come back. If that doesn't work do the same on the manual headlight switch on the column. Also try spraying some electronics cleaner into the switch to clean up the contacts.
If either solution works you've identified the problem. If it keeps reocurring it may need a switch change.
Any lighting related DTCs?
I had the same issue a few months back. The contacts in the multi-function switch that control dash and running lights were no longer making contact. Replace the switch and your problems will be solved! It takes about an hour or so to swap the switch. Alternatively, you can fix the switch (check out this THREAD). This is what I did. 
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
Have a 99 C5 Convert. and when we put the lights on, all we have are headlights. No parking, running or dash lights. But if we turn on the Twilight it all works till we shut the vette off. No blown fuses, relays seem OK. All grounds seem clean and tight. Any suggestions.
