Has anyone else experienced this....

A couple of times this summer when I had just gotten my FEH 08 I noticed that once the engine had warmed up, it would shut down at stoplights even though I had economy mode OFF and the AC on. It seemed like I could correct the problem only by turned the car off, waiting a few seconds, then turning it back on, and sometime would even have to couple this with turning the AC off and back on again.

Now, during the winter months, I have noticed this is happening pretty much all the time when the outside temp has been significantly LOWER than the desired inside temp- even though econ mode is off, and I have AC on, the engine shuts down at low speeds and stops. However, when it recently warmed up, the controls went back to behaving normally and the engine will stay on with the AC without economy mode on.

Recent events make me think that it's tied to temperature outside and the need for the engine to run for the AC to get the desired air inside, but I am still weary of it because it has happened during warm weather as well on occasion and I am left with hot air blowing in my face.

Has anyone experienced this?

 

Sounds like you have a bad switch, relay, or logic board.

Sounds like it is time to have it looked at by a qualified service center.
If you are under 36,000 miles, it should be fixed free of charge.

HTH,
-John

 

Does using a 'red' defrost button keep the engine on? Altho I have experienced that even with it on, once in a while it'd still go into ev, but not often, I guess if everything is warmed up enough?
If hitting a red button turns the ice on, it could just be the switch, hopefully something easy to fix.

 

I noticed this too in my 09 that with the defrost on it'll go EV and I'll get engine cut on the highway, but not all the time. I haven't noticed a pattern when it will and won't. Is it necessarily a bad thing going EV with the defrost on?

 

I remember reading on here a long while ago about being able to EV with deforst if X condition's are right. Sadly my brain left the X out, but I think it's above freezing temps. A search might turn it up, or that person may post again, sorry I don't remember.

 

Econ mode is SOLELY for the purpose of sacrificing A/C COOLING capability in return for improved fuel economy. Basically when you use econ mode you are agreeing to give up some level of human comfort in return for FE.

Note that I said "sacrifice COOLING capability".

Econ mode will still run the A/C for DEHUMIDIFICATION, defogging/demisting the windshield and/or windows and keeping them defogged/demisted. Obviously COOLING, although sometimes undesireable, will be a side effect.

All automotive systems MUST disable the A/C if the OAT is below about 34F in order not to freeze up the condensate on the A/C evaporator and therby block all incoming cabin airflow.

So your ICE, can ignore the econ "rules" below that temperature.

And filnally..

Once initial cabin cooldown is accomplished it would be patently foolish....FUELISH, to run the A/C in when the OAT is below your cabin air temperature setpoint. If the FEH/MMH/Tribute didn't initially have this latter A/C "economizer" mode I wouldn't be surprised if a reflash is available, or was made available, to make it so.

 

All of model year 2005 FEH would not shut the engine off ever, if defrost was selected. Exception: during an ABS event the engine will go off, then come back on after ABS ceased.

I think early 2006's had the same "firmware".

Sometime, between 2006 and 2007 this was updated to allow ICE off in defrost mode, if other conditions, such as freezing temperatures were present.

HTH,
-John