Strange (?) cooling problem.
 

Daughter's 99 LX sedan AT 4 cyl.

Overheated while sitting in the drive through line at the new In-n-Out last weekend.

Was fine while moving but would overheat when standing still.

Tried to reproduce symptoms today and observed the primary cooling fan come on after a bit of idling in the driveway. Drove it a while and was having trouble getting it to overheat. Did notice that the air blowing from the vents was hot with the dial turned to cool.

Turned the A/C on and idled it for 15 minutes. Still no overheating but this time the main fan was not on.

Drove home and sat it in the driveway a bit and it finally started to overheat. The main fan was NOT running. Shut the engine off to prepare to meter the voltage at the fan and it CAME ON. The fan comes on as soon as I turn the ignition off but not while the motor is running. The fan seems intermittent with the car running but comes on immediately when I turn the ignition off.

BOTH fans should be running when the AC is on. BOTH fans should come on when the ac is off and thermo a gets to ~ 194*. So, pull the connector from thermo a, green plug on the T-stat...not the upper hose. Jump that connector with the car "on"-not running just key to on or pos II. Do both fans run?

Then with the car on-again not running just on- turn the ac on-do BOTH fans run?

Fans
 

Both fans do NOT come on when jumping out the T-stat sensor. The primary does put not the condenser fan. Next step? Oh wait. I just thought of something. I'm gonna check fro Dd voltage at the condenser fan.

Fans
 

11.77 VDC at the condenser fan. I'd like to see that a bit higher but the battery is a bit weak. But its there. Guess it's time for a new fan.

If ground is good, yep...fan motor time. Thanks for getting back, many times you never know what happened, and it helps everyone in the future that might run into the same issue.

Related!! My radiator fan (pass side) does not come on when I energize the system (on but not started) cold and then starts when I shut the system off!! What's up with that ??

"Bills"- how are you "energize the system". Also would really be best to start a new thread, you might have and I just haven't made it there yet as I work from oldest to newest.....then PLEASE tell us what car you have...notice how utupelo and I both have a signature line that list what cars we have...or at least the Honda's we might be working on.


utupelo..happen to be in or from MS, finally made the connection....I lived in Memphis for years....70's thru late 90's.

Hi, Energize the system is to turn the key to the on/run position. I have a 91 accord ex wagon . Good advice. Thanks

Billswagon,

What year/model, etc.. accord do you drive? Put that information in your signature, so we know what you drive.

Bill-does the ac work? If so then key on, ac on, blower on - should make both fans run. Is all of this true?

If the ac does not work, you'll need to jump thermo/switch A and turn the key on before both fans run.