mctabares

Has anyone installed a fan override switch on the dash to manually switch them on in hot climate and heavy traffic and keep engine temp. down, and if so what are the wiring connections needed.
Thks.

Mtabares

BADDUCK

I haven't wired one up myself but you can buy a kit already made up from Mid America and other Corvette suppliers. Those kits will work on a 1991 but uses a sensor to automatically turn on a fan at a lower temp. On my 1989 I just changed the sensor, no wiring kit required.

CFI-EFI

You can simply run a wire from the primary circuit ground terminal of the relay for the fan you want to control to a toggle switch. Run another wire from the other terminal of your toggle switch to a good ground. When your toggle switch is in the "Off" position, the ECM will control your fan as normal. With your new switch in the "On" position, the fan will be on whenever the ignition switch is "On". There are many, many, other was you can do this, too, but the above may be the most straight forward and simple.

RACE ON!!!

HGN CRVZ

I have a 91 and what I did was to get a double pole double throw (DPDT) switch, any type/style you prefer, mount it, then run 4 (four) 20 awg wire from the relays to the switch location. I used blue for two of these wires and black for the other two. Install spade female terminals on the two blue wires and males on the black two. On the other end of these wires put female spade lugs on all of them. Make up two more wires with female spades on one end and ring lugs on the other. Ground the wires with ring lugs on them close to the switch. To connect the switch;
1. Put the black wires from the relay on the wiper or output of the switch.
2. Put the black wires from the relays on one of the inputs.
3. put the black wires from the ground on the other inputs.

____Stock blues to computer______
Relays---New Blue wires ----<
-----New black wires to ground-----

So what is happening is that you are replacing the computers control of the relays with your manual control. The computer simply grounds the blue wires currently going to your relays and energizes the relays based on the temp sensor. You are simply energizing the relays at will with the same signal the computer uses, no harm no foul and it can be removed at will and returned to pure stock condition.

I hope this helps

SunCr

Beaten to death, but I have to admit that I did this back in the early '90's and have long since ripped out. Stock is fine - Nothing built in the last 20 years is any diffferent and the Z06 that just blew your doors off probably did so at 212 or so. If you can't keep it between the thermostat and the threshold for fan operation, there are other problems: plugged up (and probably crapped out) radiator or air flow - too much resistance in the wiring so that fans aren't cranking at what they should be - tired alternator - plugged up a/c system and so on and so forth. Assuming it's stock, why not fix it right?