Red "Performance" mode versus White "Performance" mode?

I believe red "Performance" means hot and power limited. Mine shows up briefly now and then and then goes back to white.

Do you have two single blowers or one blower motor with two fans? See here:
Roadster Rear Blower Maintenance

I have two single blowers. I'm curious about upgrading to the larger, single blower to get more airflow.

I too have noticed this when switching into Performance mode. However, I've only seen it after driving for awhile (20 - 30 minutes of spirited fun in Standard Mode) and the PEM temperature is just below the two orange increments on the temp screen. Perhaps it limits power when the PEM is in upper temperatures?

Do you have the single motor or dual motor fans?

I noticed it a lot today. It only takes a few hard accelerations in performance mode before the color changes. On the temperature display, the PEM is still blue, but at the highest blue level.

DeedWest said:

I too have noticed this when switching into Performance mode. However, I've only seen it after driving for awhile (20 - 30 minutes of spirited fun in Standard Mode) and the PEM temperature is just below the two orange increments on the temp screen. Perhaps it limits power when the PEM is in upper temperatures?

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I have a 2.5 with dual fans. Yes! The highest blue increment of the PEM temperature gauge is usually where it'll change to red upon switching. But as mentioned before, I've only noticed this on very hot & humid days (I live in Dallas) after driving consistently for a bit.

I remember reading that thread too about a month ago! Now it seems to have disappeared...

I'm getting it pretty easily on an 80 degree day. That doesn't seem like particularly challenging weather. I have the older fan setup.

DeedWest said:

I have a 2.5 with dual fans. Yes! The highest blue increment of the PEM temperature gauge is usually where it'll change to red upon switching. But as mentioned before, I've only noticed this on very hot & humid days (I live in Dallas) after driving consistently for a bit.

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Doug_G said:

There's an old discussion about this somewhere, but I haven't been able to find it. Essentially the color does indicate whether you have full performance available or not.

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Sorry to crash a Roadster thread, but I think this connects...

We've seen pictures of (IIRC) red speedometers on P85Ds at high speeds, whereas on the S85D the same speed isn't indicated in red. Is Tesla carrying on this tradition of red meaning "overheating or limiting at play" in the Model S firmware?

Are we discussing something different from the 'power limited' light? My 2.5 has shown that a few times. I figured that the red lettering in the touch screen was an indication that the new mode hasn't taken hold yet. That is, it may take a few seconds or the right conditions to be present to change modes. A continual red 'Performance' display would, IMO, indicate that you have not yet switched to that mode. Consider, say you are in range mode and low on battery and you try to switch to performance mode, you would then immediately be out of charge because you're in the last 10% or so of battery. In that case I would expect the car to not switch modes but stay in range mode. This is the kind of thing which makes modes a problem.

As Doug stated, in normal conditions (battery not being low, etc), the indicator only stays red when the heat buildup is too much.

In my case, it's usually the PEM that's in the upper temp range after some spirited driving making performance mode turn red. As soon as the PEM cools, the car switches back to 'white' mode and full power is available. In (relatively) hot weather (sunny 72F or up), having done some driving for 10 to 15 minutes and having done one or two 0-60's in perf-mode, the PEM tends to get back hot really fast after cooling back into the 'white zone' and 'red performance' tends to come back on quite easily.

The PEM turns hot by accelerating (and decelerating using the motor). A constant speed tends not to heat up the PEM that much.

As far as I can remember the old thread correctly, the available power and torque in 'red performance mode' is close to 'standard mode' power and torque.

If the car doesn't switch easy to 'white performance mode', and the temperatures are moderate, battery is full and if you haven't been driving spirited, you might have a problem with the cooling of the PEM. The fans of the PEM have been known to getting clogged up as it sort of sucks in a lot of dirt from the road. That's why the PEM usually is cleaned at every yearly service call by your local SC. This might be the case with your RS Habious. You might want to check the PEM temperature regularly to see if it stays hot too long even with the fans blowing like crazy. If that's the case, a nice cleaning might do the trick.

Habious said:

I've recently done exactly this - I was in Range mode and was somewhat low on battery (but 3 miles from home - a well-planned trip, thankyouverymuch) and I tried to switch over to "Standard" mode, but ended up switching into "Performance" mode. As soon as I did, the car bitched to me about the battery being low and that power was limited. I also got the "Power Limit" light on the dash.

But, my original post wasn't about that. I was thinking the same as you...the red "Performance" mode lettering meant that it was switching over to Performance mode and it hadn't taken hold yet. Not until it was white that you were actually in "Performance" mode.

And, if that's the case, I think I have a problem...because there are times when it simply does not ever go white. And, like I stated in my original post, this happens when things are...normal. 75° F out, car hasn't been driven hard, battery isn't super-low (or max charged). I'm not getting any kind of an error message, I'm just not getting a white "Performance" mode.

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My Roadster has the same issue. It is a standard model though (not a sport). Even on cool days I don't recall the letters staying white for very long... perhaps my PEM is less capable than a Sport one? Right now the PEM is dirty so it doesn't take more than a single blast to get red letters.

Mine is a non-sport too. As the PEM is air-cooled, the outside temperature plays a big part in the PEM turning red. With temps at or above 28C mine doesn't take much to get (and pretty much stay) in the red too. With temps like now (at or around 18C) the PEM is fine and doesn't get in red letters very fast.

Habious said:

It seems to me like there should be SOME sort of filter on that blower. I've crawled up under there a few times. The blower is easy to get to. Once the road crap gets sucked up into it and blocks the PEM vents... keep out the leaves and the freakin' rocks! What am I missing here?

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Agreed! .... I did this the simplest way I could think of..
Roadster Rear Blower Maintenance - Page 6
(other solutions are available )
Its working GREAT... coupled with a prior clean out.. Leaves, dust etc.... But in my case no rocks!!

Habious said:

I wanted to make sure this thread came full circle, so here's an update...

- The car started out as I mentioned in my original post - it wouldn't say in "white" performance mode.
- Then it got to the point where it wouldn't go into "white" performance mode at all
- Then it got to the point where it was at the upper end of the PEM temp range
- Then it got to the point where I got "The PEM is freakin' hot" on the VDS (I'm paraphrasing here) and I got the "Power Limit" light on the dash

I took it in for service this week. They just did a service on the PEM blower. The "Roadster Guy" said that it was all gunked up with road stuff - leaves, dirt, rocks (rocks!?!?!)

$295 (and 4 days of Roadster-free driving) and I was on my way again.

It seems to me like there should be SOME sort of filter on that blower. I've crawled up under there a few times. The blower is easy to get to. Once the road crap gets sucked up into it and blocks the PEM vents...not so much.

I feel like some tie wraps and a couple of pieces of cheesecloth would be better than absolutely nothing. Yeah, it's not a 2 micron filter but, it would keep out the leaves and the freakin' rocks! What am I missing here?

I think the worst that could happen is the cloth gets clogged up with junk and restricts airflow but, that's happening anyway.

FYI, my car had the PEM replaced and it was serviced all of 4 months ago. The annual was done in October. I've only put about 5K miles on it since I got it (in October, right after the annual).

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Several of us have fashioned filters from high-flow furnace or AC filter material. There's at least 2 threads on this. You have to make the surface area large so when it starts to get clogged up it won't restrict air flow. But like you said, nothing can get clogged up as bad as the system does with no filter. I thought the snow dam would work, and it helps, but it isn't the whole answer.