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P0116 CEL AC Off issue

telemike

Hummer Enthusiast
Messages
466
Location
Greensboro, NC
The H3 just threw this CEL. Where is the ECT sensor at? I want to check connection first. Anyone know what this code might be?
 

f5moab

Mr. Beretta
Messages
2,000
Location
In hiding.....
Right rear (passenger side) of cylinder head. Checking connection would be a good idea, but also make sure your coolant bottle is filled to the correct level.

ectsensor_zps471f404f.jpg
 
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f5moab

Mr. Beretta
Messages
2,000
Location
In hiding.....
Is 116 the only code? Usually, hot always, this one sets with 117 or 118.
Basically it means the ECT is not reading a correct correlation with the IAT (intake air temp) sensor. It watches the IAT and ECT over a period and will determine which one is actually acting crazy.
 

Hunner

Well-Known Member
Messages
2,334
Location
Arkansas
I might suggest if you think you have an overheating problem that you try filling the radiator directly even though the tank is at the proper level. Then see if other things are causing it.
When I had a heater hose thru the firewall that the clamp was loose on, it only allowed coolant out at high temps and then did not appear to leak. It overheated and thru that code and just about every other code there is and went into limp mode.
We finally had to fill the radiator directly as it would not pick up what was in the tank.
F5 and Neo rescued me by bringing vital fluids:emb:!!
 

ArtHummer

Well-Known Member
Messages
1,220
Location
Gaithersburg/MD
If it's hot. do not open it. Let it cool down and then cover it with piece of close. To open it you need to push down on the cap and turn it under-clockwise.

Also, if you clear the code an it comes back on, i would start with replacing the sensor. Could be just that the sensor is bad.
 
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telemike

Hummer Enthusiast
Messages
466
Location
Greensboro, NC
Since I don't have time to mess around with this now because I am working 50-60 hour weeks, I just dropped off at a Dealer. Will post updates.
 

f5moab

Mr. Beretta
Messages
2,000
Location
In hiding.....
At the dealer. Tech says the IAI and ECT sensors are not agreeing. Have to wait for parts to test and see if it clears.

Sounds familiar.:) I guess "not agreeing" is a technical term meaning "not reading a correct correlation." :giggle:

But what parts? This is not hard to check.
The PCM reads both these sensors at startup. If the engine has been off for a set time (approx. 8 hours) the PCM assumes the ECT will be within a +/- figure of the IAT. If it sees a larger variance, it is then programmed to watch and learn. Does the ECT go up from startup to what should be a good reading. The PCM will also look at the rise/lower in temps of the IAT. Under most circumstances, the PCM will determine which sensor is bad; thus the code it will set.

It is very easy to check the resistance across the sensors. If it is intermittent; about all that can be done is the one sensor be replaced.

Also, if a ECT is intermittent, you may feel the engine running like **** on a cold day and if you look at the temp gauge it shows the temp really low but the engine has been running for quite some time. In fact, in some cases, if it is really cold and the engine is really hot, the engine might sputter. It is running too rich.
 

Calamitygirl

Born to Wheel
Messages
447
Location
Wyandotte, Michigan
Solar has the same scenario as described above. AC Off code, flashed one time on the way home. The thermostat needle did not budge from "L" and I was highway driving for a solid 40 minutes. No more warranty on Solar, she recently turned 100,000 (I can't believe it). 2008 H3 Adventure package.

Is changing the sensor easy like changing a fuse? Or bite the bullet and take it to the dealer?
 
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