Hello-

Just bought my second fourth-gen car, a 2000 BGC Firebird that is very low-optioned. Any idea what the point of the T78 RPO is? Best I can see, there is no light behind the light switch which seems more trouble than it is worth.

Thanks for any insight!

 

Not sure, but I think that may be typical for the US models, deleting the "automatic" headlights required in the Canadian models. There are vague references in this thread:

2002 Headlight Malfunction - Fourth Generation Pontiac Firebird (1993 - 2002) - Firebird Nation

Note post #3.

[EDIT] Look at page 2-53 of your Owner's Manual for a description of the Canadian automatic headlight operation.

 

Thanks Fred. I thought it was odd that there does not appear to be a light bulb behind the switch. Is this typical for RPO T78? Or an I not knowing where to look? I pulled the control out and there did not appear to be a place for a bulb. First Firebird and a little bit different than my 94...

 

I don't know the specifics of each model of each year, but if I had to guess, I'd say the illumination is integral (not a replaceable part) with the switch. Can't say that for sure. I doubt that T78 deletes the illumination. The factory manual wiring diagrams shows a bulb inside the outline of the switch, for all the production variations (domestic, Japan, Scandinavia, European, etc).

You can download a factory service manual here:

LINK: 4TH GEN SERVICE MANUALS; 82-02 PARTS DIAG; 99-02 WIRING DIAG - Fourth Generation Pontiac Firebird (1993 - 2002) - Firebird Nation

 

Thanks Again Fred!

 

The T78 option replaces the light sensor in the top of the dash with a jumper at the DRL module. That prevents the automatic operation of the headlights in the daytime. Pretty much all GM Firebirds in the US after a certain date have that option installed. My 98 TA has it.

 

Thanks for the info. I only had one other reference point and their 2001 firebird did not have the T78. GaryDoug - Does your switch have a backlight? That was the main issue I was chasing as mine does not light and I wasn't sure if it was by design with the T78.

Thanks!

 

Yes, the light in my headlight switch does work. Firebirds sold in Canada do not have the T78.

 

Sounds like I need a new switch and I am in business - mystery solved

Thanks All!