Hello,

I just purchased a 2006 FEH (actually a MMH, but that forum is not active) and it is not consistently going into EV mode and it is making some weird noises that I noted below.

Prior to today it had not gone into EV mode or shut down the ICE while stopped since I got it several days ago.

Today I put in into "L" driving mode and then into neutral and tapped the brakes twice.

((Two questions related to this 1.) What does this actually do? 2.) When I do this I hear a temporary clicking noise that sounds like it is coming from behind the dashboard or inside the engine bay. What is this? Is this the ICE trying to shut off but not? Is this normal?))

Approximately ten minutes later I came to a parked stop and the tachometer went into EV mode and the ICE did shut down. At this time I did not shut the vehicle off and I drove it around for three minutes in EV mode (it did come out of and go back into EV mode during this time), and then once it came out of EV mode the final time it would not go back in.

I shut the car down for ten minutes and then it was back in EV mode when I started it, but once it came out of EV mode it would not go back in again.

I have researched my issue last night and narrowed this down to the following possibilities:

1.) Failing MECS pump
2. The air-conditioning lines to the hybrid battery pack have developed a leak.
3. Blend door issue--there is a vent from your split window found on the driver's side of the cargo area that goes down to the battery pack. Cooler air is drawn down into the hybrid battery pack. There is a trap door that sometimes becomes stuck or the plastic hinges wear out and prevent cooler air from being drawn down into the hybrid battery pack.
4. Internal hybrid battery pack fans have failed.
5. Filter in the rear of the vehicle

-I did pull the filter out of the rear and it was filthy so I cleaned it out as good as I could, put it back in, and I have already ordered a new one.
-The MECS pump has already failed on this vehicle and been replaced just recently under warranty at a dealership. (Could this failing have damaged anything else?)

After I turn the vehicle off and turn the key back half way on I can hear at least one fan blowing in the back by the battery.

I am also having an issue with the keyless entry, sometimes during the first time unlocking the car for the day when I click the unlock button it causes a clicking noise in the car for several seconds. It sounds like someone is holding down the unlock button or like it is repeatedly trying to unlock the doors, but it also sounds similar to the clicking sound that is made that I noted above when I put the car in neutral and tap the brakes twice. I am not sure if it is related.

The car is averaging a combined 30 MPG that is with a lot of highway driving. I feel like I can tell that the hybrid battery is being used, just not entering complete EV mode.

The charge/assist gauge on the dash hadn't moved much when braking or accelerating in driving prior to today (moved just a little). It seemed to move a lot more today prior to the car going into EV mode for the first time.

It is about 85-90 degrees outside today, and the above driving exercises were performed within 10 minutes of starting the car for the first time today. At all times the AC/defrost were off.
I have also read that sometimes the hybrid batteries need to re-calibrate/adjust themselves, could this be what is occurring? I am not sure how consistently this vehicle had been driven in the last few months.

If the Actuator in the rear going to the battery were the issue here, could it still be bad without throwing a code or light to the dash board?

Any insight would be greatly appreciated. If you could also direct me to some posts or provide guidance on how to troubleshoot items #2 through #4 listed above that would be helpful.

 

Update to this post, still seeking input:

-car makes clicking noise when it should switch to ev mode while going slow, double tap brakes, or unlock car before it is started

-if double tap brakes and it does clicking it will sometimes later go into ev mode during that drive. But it will make clicking noise before going into EV mode (below 30 mph and 2k rpm) aka Does clicking noise when it should be going into EV mode or before it does. Definitely seems related. Clicking can be heard from the exterior of the car, and also seems behind the dash.

-Noise and EV mode are definitely related. I have read the clicking sound may be related to the brakes, so it all may be related?


troubleshooting update:
-Car has had MECS pump replaced recently
-I can hear the battery fan(s) on in the back

-I replaced the filter in the rear of the vehicle



This leave the common blend door as the last issue or something wrong with the rear AC, unless it is more related to whatever the clicking noise is.


I have also read the clicking noise is normal for the brakes to pressurize. Noise sounds like a it is cycling through being unlocked or like someone is hold the car unlock button down.

 

You might check the temperature of the hybrid battery pack by putting your hand on it under the cargo area carpet. At some time when the vehicle fails to go into ev mode when it should, check the battery temp. If it's hot (it won't be hot enough to burn your hand) rather than air temperature or warm, then there's something wrong with the a/c system. It's designed to not use the battery if the battery reaches 100F.

If the battery is hot, AND the interior a/c doesn't work, then there's a problem with the a/c lines, compressor or condenser. If the battery is hot and the a/c works ok, then there's a problem with the rear battery hvac system.

If the battery never gets hotter than warm, then the problem likely is not in the a/c systems.

 

Was there any resolution to the issue of not going into EV mode?
I have a similar issue. Replaced the MECS pump, and blend door actuator. I noticed that after the battery warms up above 100•F the truck will not go into EV mode. Also noticed that during this time the blend door doesn't close and remains open (90% of the time).

I'm getting about 100kms less per tank than my summer usual of 600-650kms...

Any help would be greatly appreciated.

 

The dealership said it was the fan(s) on the battery as well as a battery harness on the battery. Hope that helps.

 

Wow, really! So the AC cooling fans in the engine bay stopped running intermittently after they serviced the fans and the harness of the battery pack?
What exactly did they do?
Thanks for the post.