Overheating

[Vip]

So my wife drives the roadster as her daily driver.
Last week my wife was driving to work after dropping off my son at school. The roadster threw up a warning "Powertrain problem, Service required" She texted me about while I was at work. A couple of miles later it put up a another warning "System too hot, Vehicle shutting down". At that point the vehicle came to stop and she could not restart the car. After trying to figure out what to do we finally called our insurance roadside service to tow the car to the service center.
They worked on it for a day and came up with the diagnosis of "fan cooling duct to power electronics module loose and not allowing full fan air volume to cool module"
I figured since the car was in the shop I told them to go ahead and do the annual service (18 months since last service) to make sure nothing else is wrong. I also asked them to change the transmission fluid along with the coolant.
Got the car back 3 days ago. I drove it from the service center to my house with no issues. My wife drove it the next two days without any issues. Then today she is driving and the powertrain warning comes up again. Luckily she was close to her destination and was able to make it there. After about an hour she got back into the car and was able to drive home (8 miles) without any issues and no warning. Told her to drive slowly and take back roads. She plugged in the car when she got home.
I get home late tonight from work to see the roadster charge port flashing red. Screen had a couple of faults "system too hot, vehicle shutting down" and something else along the lines of system too hot charging time increased. The car had charged about 40 miles in 7 hours on a NEMA 14-50.
I hear the coolant motor going so I decided to take a look. I see the coolant running in the container. When I try to get a better look to see how much is in there and it is nearly at the bottom (below the minimum line).

So I am not familiar with coolant system but I am guessing that the amount of fluid in the container should be higher despite the pump running, am I correct in assuming this? I had the coolant drained and refilled for my annual service.
What I am confused about is that the car was running fine for 3 days before this occurred again. Can the car run fine for a few days despite the coolant being low?
Any major damage that could be permanent with all this overheating?
Anyone else had this problem?
Just for future reference can I fill the coolant container myself?

I am obviously calling Tesla in the morning to see what can be done.

 

[gregd]

I would guess that the PEM fans aren't working right. Did you happen to see what the error code was?

Do you have a 1.5 or 2.x car? On the 2.x (not sure about the 1.5's), the connector that powers the fans is a bit under-sized, and the contacts tend to get burned and fail, especially over time with repeated re-connects (e.g. the annual service). The connector is under the PEM, on the passenger side. Really hard to get to. It could also be the fan motor itself.

The errors are usually 1144 or 1146, but I suppose others could occur. See: #1146 DMC Motor Fan Problem?

 

[Vip]

I would guess that the PEM fans aren't working right. Did you happen to see what the error code was?

Do you have a 1.5 or 2.x car? On the 2.x (not sure about the 1.5's), the connector that powers the fans is a bit under-sized, and the contacts tend to get burned and fail, especially over time with repeated re-connects (e.g. the annual service). The connector is under the PEM, on the passenger side. Really hard to get to. It could also be the fan motor itself.

The errors are usually 1144 or 1146, but I suppose others could occur. See: #1146 DMC Motor Fan Problem?

I have 2.0.
The system too hot, vehicle shutting down code was 947.

 

[Roadster]

Just for future reference can I fill the coolant container myself?

Yes but make sure the coolant is Propylene Glycol (PG) based. Thx to @Carl W for pointing that out to me.

 

[gregd]

I have 2.0.
The system too hot, vehicle shutting down code was 947.

Checking the VDS Code WIKI page (Roadster VDS Messages), I'm still thinking it's the connector. Too close to the service event where they have to disconnect that connector yet again. Or, the ducting fell off again.

Please let us know what the service guys find!

 

[Vip]

So my original post was last night when I got home. This morning I went to see what was going on. I did not charge the car overnight given what was going on.
The fault stating Powertrain Problem, service required still was there.
I decided to test drive the car around the block.
I started to drive and had the screen set to the temp indicators. Before driving the PEM was already at the highest green light before turning yellow. I was just about to pull into my driveway when it indicated that the vehicle was too hot and shutting down and I saw the PEM temp go yellow.
There I am sprawled across the road and can't move!!! Luckily I was able to put it in neutral and push it onto my driveway.
So I am seeing 2 codes: 947 and 1144.
Tesla is currently trying to figure out how to get the car to there service center.

 

[ShawnA]

Hi Vip,

Do you know if you have the 2 motor 2 fan setup?
Or the latest 1 motor in the center serving the 2 fan/blower units?
If you have the older 2 motor 2 fan setup you may be able to see or hear if
either blower is running...

The Sierra Antifreeze may be hard to get locally, but it is available on Amazon...

Shawn

 

[dhrivnak]

The Sierra Antifreeze may be hard to get locally, but it is available on Amazon...

NAPA sells it in my area, check with them first.

 

[Carl W]

I couldn't find the coolant online or any store so I ended up bringing an empty antifreeze container to a tesla service center and they filled it for me for free.

 

[Vip]

Update:
To answer ShawnA's question. Tesla told me I have the 2 fan setup. And apparently this is what is wrong. Not sure what happened when it went in the first time and was not discovered.
Tesla stated there is a recommended fix for this, to change it over to a single fan with different components. Unfortunately the cost is $1600!!! Not too happy about that given I just dropped about $800 the first time around which was basically the annual service.
There goes the gas savings for the year!

 

[ML Auto]

The dual fan unit works fine as long as the connector on the PEM doesn't burn up. That connector has a limited life, and gets unplugged and reconnected when the PEM is removed for cleaning. The new single unit draws less current through that connector and apparently solves that issue. The dual fans are only about $75 each if your problem is just a bad fan. The single fan unit is around $200, but requires a new mount and reprogramming of the PEM for 24V. So its Tesla only if you go that route. And $1600 to fix their design flaw is a big slap in the face if you ask me.

 

[Jonathanm]

A couple of things...AFAIK there is also a torsion bar that needs to be changed and secondly I thought they were changing these fans out for free - as MLAUTO says...it is a Tesla cockup....I'd be pretty peed off if they tried that with me....

 

[DanielFriederich]

GS Technology in Switzerland has an updated cooling fans set with brushless motors.
Also too much or not enought battery coolant can cause inconsistent errors.
Did you check the Molex connector bottom side of PEM (connector to the fans). This one easily burns a bit when too many amps are drawn by the fans.
The battery coolant is sierra antifreeze and distilled water 50/50

 

[Kerios]

The single fan unit is around $200, but requires a new mount and reprogramming of the PEM for 24V.

Don't see why? It's not a 24v bus, it's 12v - it's a rare car which has a 24v secondary circuit, big trucks and buses etc operate at 24v, but the Tesla dual SPAL fan is 12v. The fan unit code from the Tesla one is: 014-AP74/LL-22-12V, I sourced one separately after mine had a bearing failure, cost about $180 for the dual unit with three year warrenty. Dead simple to fit, you're changing basically a twin harness (for the original two fans powered separately) into one harness - personally if I did it again I'd use a better connector e.g. IP68 compliant than the "thing" that Tesla use.

So no reprogramming and no 24v required. and more to the point you can do it yourself. If you need some help PM me.

 

[gregd]

It's been reported that the single motor / dual fan setup runs from 24v, and that 24v is created by series-stacking what were a pair of 12v drivers, one for each of the original fan motors. The firmware change would be to properly control the pair of drivers as one, instead of independently for controlling the cooling of the PEM and drive motor.

Are you saying that the single motor is actually a 12v unit, not 24? How are the fan drivers wired?

I bring this up, because one of the solutions to my car's cooling problems ended up being that the fan harness was incorrectly wired at some point in the past (I'm guessing it was when the dual motor was upgraded to single), and that was the cause of the lower than needed cooling, and possibly the earlier issues with burned connector contacts. They rewired it under Goodwill, and that significantly lowered my PEM's running temperature.

 

[gregd]

Oh also, according to the service folks, note that the PEM has no way to actually measure the air flow; it only infers it from the temperature and the speed it thinks it told the fans to run at. The fans have no tachometer, either. The 1146 errors are when what it thinks should be happening doesn't match with reality, deducing (not measuring) that the fan speed is low or there is an issue with the free flow of air.

 

[ML Auto]

I believe the errors pop up when the voltage on the line gets out of spec. Either from too much or too little current thru the fan motor. While I was playing with the ESS cooling, I got flow errors when the coolant pump cavitated while in a tank out of the car, so it was obvious the voltage or current was being monitored.

It would be good to know if the single fan upgrade is 12V or 24V, as two people have reported differently. All mine are the dual fans, so I have nothing to compare to.

 

[Rotarypower]

The later model SPAL single motor dual fan unit is 12 volts. It is clearly labeled as such on the unit itself. Please see images I posted in this thread....

PEM cleaning now higher temps?

I believe the two connectors are coming from the fan motor drivers but go into a harness that results in a parallel circuit, combining the current from the two original motor circuits into one. I can clearly see where they must splice the wires into one, as you have two connectors, 2 wires each, terminating into the motor housing as only 2 wires.