1972 Corvette - Radio Does Not Work With Key in Accessory Position

[Roger D.]

Folks:

My brother and I are continuing to troubleshoot electrical bugs after full body off restoration of the car.

Here is the next item on the list.... The radio does not work with the key in the Accessory position. When you turn the key to all the way to on position, the radio works. We've looked online, thru the Assembly Information Manual, Service manual, schematics, etc., and are unsure what to try first. Could the issue be with the ignition switch itself? According to the pictures I've seen online, the ignition switch has 9 copper terminals where it appears either individual wires or a wire plug is connected. Could the issue be with one of the terminal connections? Also, tracing the schematic (I don't have it available here to view at moment), it references a radio capacitor. We have been unable to locate that or find any reference to it online or in the online Corvette stores.

Any help in getting started troubleshooting this issue would be appreciated!

Thanks!

Regards,
Roger

[Richard M.]

Re: 1972 Corvette - Radio Does Not Work With Key in Accessory Position

Roger, I just looked at a 1972 wiring diagram. For some reason it doesn't show the Radio Power connector. It only shows the dash lamp connector.

I think the Wiper Motor and Heater Blower are also fed from ACC. Do those work in ACC? Check voltage at fuses(both ends) for Radio, Wiper and Heater with IGN=ON then ACC=ON.

The IGN switch Brown wire is the ACC output wire. If you can get at it check voltage there in ACC=ON. If it's there, you may have a problem at the backside of the fuse panel or somewhere between IGN Brown and the fuse panel.

Rich

fuse panel photo from Wilcox site...http://repairs.willcoxcorvette.com/1972-fuse-panel/

[Roy V.]

Re: 1972 Corvette - Radio Does Not Work With Key in Accessory Position

This older thread may help, the pictures, however, no longer show up!

https://www.forums.ncrs.org/showthre...adio+capacitor

[Roger D.]

Re: 1972 Corvette - Radio Does Not Work With Key in Accessory Position

Richard, Roy,

Thanks guys for your help. We were able to tear everything back down again and adjust the location of the ignition switch itself on the column so that it's location on the top of the column is now correct to be able to work with the key in the accessory position.

Regards,
Roger

[Richard M.]

Re: 1972 Corvette - Radio Does Not Work With Key in Accessory Position

Roger, Glad you found the problem. I see there are slots on the switch mount to allow adjustment. As I recall, a rod connects the column mounted Key tumbler mechanism to the switch.

1969 to 1979 Std Column switch.


That 1972 Wiring Diagram link I posted is not a very good one and is even missing the IGN Pink? wire connection on the switch. So I did more research. I found a wiring description of the switch functions in the 1979 Service manual for future reference. This switch was also used on other models.



Also found a another switch description in the 1979 wiring diagrams.