05 head light switch dim and go out - 2005 GMC Canyon Extended

bim or DIM ? the dimmer switch ! Interior Lamps
The interior lamps consists of two groups, lamps that can not be dimmed and lamps that can be dimmed. This first group consists of lamps that may not be dimmed. This includes those lamps that may be manually turned on by placing the interior lamp switch to the DOME position, or by opening a door or a compartment:
• Door courtesy lamps
• Footwell courtesy lamps
• Instrument panel (I/P) compartment lamp
• Overhead console courtesy lamps
• Reading courtesy lamps
• Rear compartment courtesy lamp
• Roof rail courtesy lamps
• Sunshade vanity mirror lamps

Interior Lamps Dimming
This group of interior lighting includes lamps which may be dimmed. This group uses a combination of class 2 controlled illumination and incandescent lamps:
• Air temperature switch
• Cigar lighter lamp
• Door switches
• Driver information center (DIC) switch
• Headlamp switch
• Head-up display (HUD) switch
• Heated seat switches
• HVAC control assembly
• Instrument panel cluster (IPC)
• Memory function switch
• Radio
• Steering wheel controls
• Window switches
For the interior lighting to be dimmed the following conditions must be met:
• A low light level has been detected by the dash integration module (DIM)
• Headlamp switch is placed in to the PARK or HEAD position
• Ignition switch is placed in the ON position
Then all class 2 displays and all incandescent back lighting will be illuminated to the level set by the instrument panel (I/P) dimmer switch. When the I/P dimmer switch is moved from MIN to MAX, all class 2 displays and all incandescent back lighting respond from minimum intensity to maximum brightness.
The DIM supplies battery positive voltage to the coil side of the PRK LP relay in the rear fuse block.
When the I/P dimmer switch is moved from MIN to MAX, then the instrument panel module (IPM), W/CJ2, or climate control panel (CCP), W/C67, applies a message to the class 2 communication circuit to the DIM. The DIM then applies a ground to the park lamp relay control circuit. This energizes the PRK LAMP relay and allows battery positive voltage to be applied through the DIMR fuse to the DIM. The DIM then illuminates the following incandescent lamps through the incandescent dimming output circuit:
• Cigar lighter lamp
• DIC Switch
• Headlamp switch
• HUD switch
• HVAC control assembly
• IPC
• Radio
• Steering wheel controls
The DIM also applies a message to the following class 2 controlled illumination components:
• Drivers door module (DDM)
• HVAC control assembly
• IPC
• Radio
The DDM will then send a message through the simple bus interface (SBI) to the RH front door module (RFDM). The door modules will then illuminate the following components through the incandescent dimming output circuit:
• Air temperature switch
• Heated seat switches (W/KA1)
• Memory function switch (W/A45)
• Power door lock switches
• Power window switches
The ground for these components are provided from the DDM and RFDM.
The following components are grounded at G200:
• Headlamp switch
• HVAC control assembly
• IPC
• Radio
• Steering wheel controls
The following components are grounded at G201:
• Cigar lighter lamp
• DIC Switch
• HUD switch

Under hood in the black box

The dimmer switch control is next to the headlight switch. Can you make the lights brighter by turning up the control ?

The globe may be in backwards. Twin filiment globes can sometimes be installed back to front. See when you have your running lights on if that one is brighter than the other, if so it is backwards, Otherwise the globe is probably getting old & blackened & need to be replaced.

Sounds like a wiring problem. Try writing to GM directly: https://www.gm.com/site-help/contact-us/email-us.html

The wiring harnesses in the plugs behind the bulbs are burned up seperate rear of headlight cover and inspect parts available at your ford dealer

You Digital dash is working as it should, it is supposed to dim with the lights on so your eyes don't have to adjust, from looking ahead to checking speed and back

Does it go completely black or just dim? Most displays dim when you turn the lights on to make the display darker so its not too bright. GPS and other displays do this. Do you have any problems with any other of the car's electronics?

To dim your head light, pull your turn signal switch. To dim your dash lights, rotate the switch by your head light switch