Our 96 Accord 190 K overheated. My wife who is very adept at listening to my car talk immediately pulled over and listened for fan noise.( Also because our other Accord 165 K had the same problem when a fan died) . The fan tested good .It turned out I had a bad ECT B sensor. To double check I went to a salvage yard and picked up several ECT B's there and I heated them up to 220 degrees and got a continuity signal.


While I was there, I noticed that on 12 Accords 94 to 97, every single radiator and ac fan had been pulled! So this must be a popular item at the yard. Do these fans die a lot? My Accord 96 is close to 190 K. The last thing I want to deal with is a bad radiator fan at an unexpected time, so while I have it apart, should I replace the fan? Rock auto carries them for $67, AC Delco/Nippendenso

 

It seems that the driver's side fan ("a/c compressor fan") fails more than the radiator fan. The terms a/c and radiator fan are misleading, because both turn on when the radiator needs cooled or the a/c is turned on.

Temperature sensor B is on the cylinder head and has a green connector. Temperature sensor A is on the thermostat housing and also has a green electrical connector. Which one failed?

The reason I ask is temp. sensor B is only used when the engine is turned off. If the engine overheated while running, then you still have more work to do.

A new fan from Honda is expensive, so I would guess that these are easy to remove and fairly inexpensive used.

FYI, if your car overheats, turn on the blower full blast outside air, and turn on the heat to highest temp.

 

The part number is 37773-PT3-505 SWITCH, THERMO (A-106)

 

You have part numbers mixed up. A-106 is 106C (223F) thermoswitch B which fits on the upper radiator hose return fitting. It only affects radiator fan on/off when engine is OFF to avoid heat soak overheating of cylinder head.

Thermoswitch A is 37773-PT0-004 (A-94) or 94C (201F) thermoswitch.

Thermoswitch A is located on lower radiator hose return fitting attached beneath intake manifold behind distributor.

good luck

 

Back to a basic question... How/when did it overheat?

Fans are rarely needed during driving - there's always plenty of air pushing through the radiator from the motion of the car. And the other thing is climate - do you live where it's cold now?

For my typical driving, I bet the fan never runs during the winter.
- typically don't get caught up in stopped traffic - I'm just lucky.
- it's COLD.

So... if your car overheated while driving down the road, you might want to look at other things beyond the fans.

 

I've been trying to answer for 2 days but my browser locks up.
The car overheated on a 50 degree day out here in Seattle.

Are you thinking its a thermostat?
-Both fans come on when I switch on the AC
-The ECT on the water outlet which connects to the front radiator hose does not show continuity at 222 degrees.
-Both relays are okay

 

Overheating while moving forward at speeds at/above 20 mph could be stuck thermostat, low coolant level, or failed head gasket (gas entering coolant).

Very unlikely to be thermoswitch A which should turn cooling fans on at 94C. Your's may be out of spec, but still unlikely source of overheating.

good luck

 

You say "radiator outlet housing ECT"... WHAT is that exactly? The radiator "outlet housing" is the lower tank, and there's no fan switch in there.

ECT switch "A" is located in the thermostat housing, roughly below the throttle body. This is the one you want, as that it the lower radiator hose (radiator outlet flowing towards thermostat).

ECT switch "B" is located in the nozzle where the upper radiator hose connects to the head. That hose flows towards the radiator, so I guess I'd call that the radiator inlet. That switch has no authority to switch anything until you switch OFF the engine. It controls the single radiator fan (not both fans) during the first 10 minutes after you switch off the engine.

 

Now, if the car overheated during 50.F WHILE DRIVING, then I'd say it has nothing to do with the fans. By the time the car is driving 20-mph or more, that pushes more air than the fans anyways.

It's been my experience that in 50.F weather, it's difficult to get the fans to run while driving at any speed.

 

Thanks everyone, you helped me a lot.

• I did test the correct ECT, its just that I'm using the Honda shop manual terminology which reverses A & B.
• I meant the ECT on the front of the engine .( I just didn't describe its position accurately.) There's no continuity between 170 to 240 degrees so I guess its dead.
• I did buy a new thermostat yesterday at NAPA.
• I found a CARQUEST radiator fan for $30 on Ebay.
• And I found an FAE ECT at Amazon.

We have two Accords (96 and 97) in our fleet of 5 older cars . Both are plus 185K. They both look tired cosmetically but I try to really stay on top of them mechanically and they both are maintained on Mobil One.


The other one overheated two summers ago. At the time I replaced both the thermostat and the AC fan, which was dead. Its never overheated again. I always thought it was the fan that stopped the overheating, but now I realize it was the thermostat.


Boy am I glad I found this forum!