Dik

Looking for a little technical direction.

My radiator cooling fan just quit operating for no appearant reason. It's a shame because this is one of the best fall/winters I can remember and I'm going to lose some driving time in my first and recent Corvette purchase.

My service manual is about one week away so in the mean-time can anyone point me to the fuse panel location and if possible offer a hint on what else to look for as a possible cause? Temperature sensor, etc?

WARNING: I have meters and know how to use them (I'm a technician...electrical/instrumentation, not mechanical...)

I'll probably run it into the shop but I'd still like to at least have a better understanding of the problem first....possibly make a quick/easy repair.

Dick

LarryMJones

Do the fans work with A/C operating. Some GM cars had a relay to activate fans when A/c was operating and a thermostat to cycle fan off at low engine temperature.

It at least lets you know if your fan motor is working.
LJ

RogerC6

If they come on with the A/C on , the fans are fine.

Dik

Excellent thought! I'll give this a try tonight.

Just so you guys/gals know, I post in the Canadian forum but I continuously lurk here for information on everything and anything Corvette and a good laugh once in a while too. And I'll take this opportunity to say thanks to the membership. A great source of information over here.

Dick

pmj341

check the controler plug at the bottom of the radiator, 3 wire plug, check the center wire, its black, the wire problably melted the plug!!

cranky

this has been a problem discussed on here before. also, the cooling fan is controlled by the BCM computer. maxi fuse is in the under hood fuse box. relay is also there. this is a problem that will require the use of a scan tool to pinpoint the problem.

BSE1956

to answer your question, the fuse box is in the passenger foot well under the mat/carpet

Bill Dearborn

Check Fuse 32 in the underhood electrical center. The cooling fan fuses are not in the passenger foot well.

Bill

cranky

Dik

Thanks for your time people.

I didn't get a chance to look at the car last night due to long project hours and a hockey game on TV (of course).

A good day to all.

Sincerely,
Dick

Dik

Crank, I think you're onto the solution. First I checked the plug then made sure the fan turned freely by hand then ran the car until it was warm. My fan does run but at a very slow speed.

If the weather stays cold (but with dry roads) I will continue to drive. But it looks like it will be off to the shop next spring.

Dick

Dik

Okay, I'm getting close to investigating this issue. Cranky, you mention a "scan tool" is required. Would a tool like the Diablo Predator work or do you mean a "scan tool" that a GM shop will have?

I'm probably going to buy one (Diablo) anyway but I'm wondering if my problem maybe resolved by re-programming the temperature that the fans start and run at.

Dick

cclive

The fan is computer controlled and is not simply on or off, so the fact that it runs slowly is not necessarily a bad thing. The computer can spin the fan at a variable speed.

Typical Canadian...lets a hockey game interfere with fixing the Corvette.....LOL

Bill Dearborn

The scan tool is used to command the fan on and off with the ignition on and the engine off so the tech can see if the fan does turn on. If the Diablo can't perform diagnostic commands (which from the descriptions I see it can't) then it will be useless in diagnosing the fan operation.

Bill

antt

Should the fan come on with the A/C? I cannot hear the fan running with the A/C on and the engine temps quickly rise when stopping at a traffic light (A/C on or off). With the engine temperature at 198ºF when stopping at a traffic light, the temperature will frequently reach 212ºF by the time the light turns green. This may take only ~1 minute at 80º air temperature.

cclive

I'm not sure if the fans will come on with the A/C if the car is cold, but once it warms up, then yes, when the A/C is switched on, the fan or fans come on too.

Mike Green9

My undestanding of the rad cooling fan is as follows:

When the coolant temp hits 204 - the fan is on LOW
When the coolant temp hits 235 - the fan is on HIGH

or

When the Engine Oil temp hits 302 - the fan is on HIGH

or

When the A6 tranny fluid hits 207 -The fan is on HIGH

When the engine is turned off, the fan will run for a max of 2 minutes if the engine coolant is 235 or there is high pressure in A/C system.


With 6300 miles of Summer driving on my 08 (A6), I have never heard the fan on HIGH, in fact I have never heard the fan at all,
although LOW may be too quiet too hear when driving.


Hope this helps,

M..

Dik

Thanks Mike.

Those temperatures seem very high to me. I'd expect to see the fans at maximum speed once the temperature reaches close 212. I understand the system is under pressure and will not boil until the temps are higher, but 235 is the highest temp I've heard from any car.

What brought me to this "potential" problem is one hot day while driving I could smell antifreeze. I thought my car burped some antifreeze out. I checked the temperature and saw it was 218. And I have been monitoring that dang DIC since! I get a very concerned when I watch the temps rise to 212 or higher.

I'll hit the owners manual before I make any hasty decisions.

Dick

cclive

212 is not high...you need not get concerned at that temp. I do not hear any fan until water gets to 219-221.

You can certainly re-program the computer to turn the fan on sooner, but it sounds like your fan is working right. On a warm day, seeing 225 on the water temp is not unusual.

Mike Green9

I have attached some pics from the shop manual which may help. Difficult (and probably illegal) to scan the manual. Let me know if you can read them:








M....