Help! quad lamp driver

[Rich Myers]

I have a 1993 40th anniversary ruby that has a bad quad lamp driver in the main computer and my chevy dealer has not been able to get a replacement for 8 months now. I feel like I am getting the runaround. any suggestions?

 

[boomdriver]

I have a 1993 40th anniversary ruby that has a bad quad lamp driver in the main computer and my chevy dealer has not been able to get a replacement for 8 months now. I feel like I am getting the runaround. any suggestions?

Start calling the speedo/ECM rebuilders around the country. To locate them, call the catalog storesor go online and see who they send their exchanges to. Plenty of Corvette catalog parts sales online.
There ARE shops that service and rebuild all form of automotive computer. You might even find one doing a google search or even the ph book. Dealerships are nothing more than a middle man when it comes to electronic repairs or programming. I'd cut them out and get it done. All its going to take is a USPS box and shipping label. Worst case, buy a rebuilt computer, exchange, w/warranty.

 

[vetteoz]

I have a 1993 40th anniversary ruby that has a bad quad lamp driver any suggestions?

Has the dealer done full diagnostics of the problem
A quote from someone who knows

"GM vehicles. Quad driver fault;
is the computer really the cure?
Probably not but, if the vehicle is early GM and has a constant check engine light with a quad driver fault code set the computer (ECM) may have became permanently damaged.
So if the ECM is replaced without any diagnosis to locate and repair the cause of the fault then the new ECM may soon become permanently damaged as well. On newer vehicles with an ECM that has protected quad drivers replacing the ECM is most often not necessary.
Just because you have a Quad driver code doesn’t mean the Quad driver is bad. All a Quad driver code means is that an expected value is not present when it’s suppose to be.

There are many different code charts out with different code definitions. Some are quite vague while others seem over complicated. Some simply state, quad driver fault, while others will state, quad driver circuit fault, sense voltage low when should show high. Or sense voltage high when should show low. No mater how the description reads when a quad driver fault is set, then quad driver circuit testing is imperative before an ECM is replaced.
Also a Quad driver is a techy name for 4 on-off switches arranged in a group, hence the name Quad driver. The computer watches the voltage values on each switch and knows that if the switch is on, a voltage value will be seen.
When the switch is off the opposite voltage value will be seen. Simply put, light on, light off.
So what can set a quad driver code? . How about a bad bulb? How about a bad fuse? The answer is yes to both questions.
Yes, a bad bulb or failed fuse can set a Quad driver code.

Start with checking your fuses. There can be up to 3 fuses that supply power to circuits controlled by the Quad drivers.
If the fuses are good the next check would be of all or some of the following, depending on how your vehicle is equipped: Up shift light bulb, coolant hot bulb, shift to drive bulb, A/C relay, coolant fan relay, EGR solenoid, Canister Purge solenoid, even a speedometer output signal goes to one of the switches on the Quad driver.
It’s more likely that the Quad driver code is present because the computer is not seeing the information that it expects to see at one of the switches."