No running lights, dash lights

**77k5** · 12-27-2009, 05:40 PM

96 Z28, I have no running lights, dash lights or fog lights, all fuses are good and have been checked with known good fuses.

Warning lights work but there is no backlighting on the dash.

Read something that said that a malfunction in the running light circuit will cause the dash lights to go out, checked the bulbs and both are good, no apparent corrosion issues (though they look original).

Any ideas?

**MonteLS1** · 12-27-2009, 09:15 PM

First of all did are you certain you found all the fuses? There is probably a fuse panel under the hood as well under or behind the dash. If they are good, it could be the headlight switch, daytime running lamp module (if equipped) or the BCM (body control module), or possibly a broken wire, if the vehicle has aftermarket accessories installed, check all of the connections, make sure that the installer didn't break any wires when he spliced into them. Also unplug all of the connectors from the module of the auto starter or alarm, and see if the lights work then. I've seen faulty modules ground a wire that supplies power to something else. I've also replaced a faulty BCM in a Firebird for the headlights not opening. But they are very expensive, you may need to go to a good diagnostic shop, the dealership is a good place for this kind of diagnosis, they usually figure it out quick, and they have the ability to put parts in and try them, and take them out and put them back on the shelf if they're wrong. Independent shops sometimes will make you pay for the misdiagnosed part as it isn't returnable.

**77k5** · 01-01-2010, 10:47 AM

No fuses are blown, any idea on how to diagnose this?

**Intimidator02SS** · 01-02-2010, 07:08 AM

Its your headlight switch.

**MonteLS1** · 01-02-2010, 06:17 PM

Well I'm a certified mechanic, so I can probably help you figure this out. I need to know if your vehicle is equipped with DRL (daytime running lamps) or not to find the correct wiring diagram.

**77k5** · 01-03-2010, 08:59 AM

My car doesn't have daytime running lamps

Thanks fellas

**ESBdieselcam** · 01-03-2010, 01:59 PM

I'd agree. Almost positive it would be the headlight switch. I've had the same problem with a pick-up truck

**MonteLS1** · 01-03-2010, 05:50 PM

Originally Posted by 77k5

My car doesn't have daytime running lamps

Thanks fellas

Well I'm looking at a wiring diagram right now, and the circuit is relatively simple. If you can pull the headlamp switch out and access the wires behind while leaving it plugged in you can test a few things with your circuit tester. The highlight switch should have 6 wires going to it.

First check the orange and red wires, each should have 12 volts with the key in any position. I suspect that's what you're going to find. Check the brown wire now, it should have 12 volts with the headlight switch in either park lights or headlights position, with the key in any position. I'm pretty sure there isn't going to be power there. Looking at the diagram, with your description, that looks like the only possibility to me. So if that's what you find, then you need a new headlight switch. If not let me know, and we'll go from there.