Jump to content

GM-TECH, Lights Out!


Recommended Posts

Posted

On my way to work this morning, 05:00 , suddenly the lights shut off!

Fornuately I had the wimpa$$ fog lamps on so I could see the shoulder. I turned the light swithch all the way counter clockwise and then all the way clockwise and they come back on. When I turned the switch to Auto they stayed on.

 

 

Failure analysis. possibilties: bad photo optic sensor, bad relay, bad switch

 

I do have my fogs. low and highs dioded together, so there is the possibility that could be a factor.

I am not aware of a circiut breaker in the light circuit that may have tripped.

 

It was foggy and I had my highbeams on. I drove into some really thick stuff and hadn't gotten around to dimming my lights.

I'm running 100 watt Hellas in the High beams. I wonder if there is a remote chance the glare and reflection from the fog caused the photo optic switch to cycle?

 

GM Tech, what's your opinion?

Posted

When the ambient light sensor fails, the headlights default to ON. While it's possible the sensor could have simply given a "it's light" signal rather than a full failure, I've never seen it. I don't know if reflection could do that. They require a pretty strong light signal to indicate it's daylight. Even driving under a bridge will cause the lights to come on.

 

There's no circuit breaker per se. The BCM controls relays that turn the lights on and they send power to the lights through fuses. I'm sure the BCM is protected against an overload condition but not by an old fashioned circuit breaker. Probably some sort of QUAD driver, but I don't have access to BCM internal schematics so I really don't know.

Posted

I have a 2001 2500HD, basic truck. And mine has done that a couple, three times for no apparent reason.

 

I did the same thing you did, flip the switch back and forth.

 

However I do not have fog lights and it was quite a rush driving in pitch blackness.

 

I have not taken it in, 'the dealer would flip the switch on and off and say everything is fine' and send me on my way. So why waste my time.

 

If you find out whats up let me know.

 

Jim

Archived

This topic is now archived and is closed to further replies.

  • Latest Articles

  • Posts

    • My brother has an Escalade. The warranty has expired so he told his wife to go to the Valvoline quick lube he uses some times. They told her if her car was a 2020 and newer 6.2 engine they wouldn’t touch it. Hers is a 2019, so they did the oil change.
    • The oil filter has NOTHING To do with oil leak. GM sources parts from 1,000's of vendors and as with anything mass produced, flaws are unavoidable.    Putting a larger oil filter will do nothing but satisfy emotions. The OEM filter is designed for the engine and perfectly capable of handling the demands on the engine. Oversize oil filter could result in reduced flow and overall lower oil pressure.
    • You're better read than that Atlas. 😏   British science fiction writer Arthur C. Clarke formulated three adages that are known as Clarke's three laws, of which the third law – that "any sufficiently advanced technology is indistinguishable from magic" – is the best known and most widely cited.   Stribeck and the pivotable Hersey Number isn't voodoo nor snake oil. That part is physics. It's what marketing and bean counters do with it that is snake oil and voodoo.    Stribeck is the relationship between Hersey and the Coefficient of Friction. Within the Hersey Equation if viscosity and viscosity is 'Dependent' on.......heat.......and.......viscosity index or the temperature to viscosity slope.    Specifically Hersey is the viscosity AT THE TEMPERATURE IN THAT LOCATION FOR THAT SLOPE.   Hydrodynamic lubrication exist when the film thickness in the location is 3X the Ra roughness of the surface. This is irrespective of the hardness of the substrate. To obtain that thickness X viscosity is required for Y velocity at Z load. That's a lot of moving parts. It is also impossible to maintain in an ICE but nearly possible with a turbine under constant load.    What does that mean? Error heavy and operate light. Wear is inevitable but the rate of wear and the milage obtainable are a function of prevailing conditions and HABITS. The only penalty is viscous drag and at fractions so low as to be well worth the effort. Double the life, half the manufacturing carbon foot print. Greed is the only impediment.    The materials generated by SwRI are the RESULT not an estimation or a hypothesis.    Don't delude yourself sir, EV's have as many pitfalls as ICE's. We just don't know what they are yet and it will take longer to sort as MARKETING and GREEDY CEO's have had more time to polish the turd they are selling. 
    • You can always count on greed to prey on ignorance and stupidity.    Friend bought a 2019 Ford Flex and asked me about using Valvoline R&P 5W30 in it. Told him give the miles on it and the fact it wasn't yet using oil that it was a good plan. He uses a Valvoline quick change shop for his oil service.   First they tell him that isn't the oil the OEM recommends. He told them he didn't care what the OEM thought. Then they floated the, "But it will void your warranty"    His reply was it's a 2019, there is no warranty and informed them their knowledge of the law was lacking.    Then they tell him 'But it will ruin your motor"!.    Mine to ruin he says. Finally they give in and charge him 150% the semi-syn price    Point it the brainwash is so embedded that even the service industry is drunk on their swill. The public is right behind them. Echoing the same lies on every forum and media platform. If the end goal is indeed EV then I'd say that ship is about built. 
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...