Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.

Damned! #1144-alert again after service!

hi folks,

i feel helpess and sadden.
two weeks without any trouble after a self made service on my 2.0 the car spontaneously announced that 1144-alert ("power train problem. service required") many times again yesterday after some dozends of miles cruising. the motor temperature was 76°/169 F at that moment and PEM showed 34°/93 F, the fan was blowing strong. so nothing to be worried about but alerts however.

two weeks ago PEM and motor were carefully cleaned and the rear fan was replaced.everything seemed to be perect after that procedure. for about 300 miles now no alerts anymore - till yesterday.

any idea what darned fault is living in my car?

Think its the coolant flow. If they are new pumps, then it's the valve attached to their link that is limited the flow.
  • Informative
Reactions: dhrivnak
hmm...i am confused... IP1144 is a typical fan problem alert. right? and the fan blow is a separate air cooling circuit which has nothing common with any other liquid coolant circuit. the front based liquid cooling system supports the batterie and air con only. very strange...

BTW: is that fault you discribed a dangerous one which prevents me from driving on or would getting it fixed on the next occasion in a service center be early enough?
Last edited:
I think cmaster is referring to a Model S/X... No coolant goes to the motor or PEM on the Roadster. 1144 is definitely related to the PEM / Motor cooling fan.

I'm assuming that you have the upgraded fan assembly (one motor, two blowers). My guess is that the connector to the PEM is not making good contact, or that the contacts have burned / oxidized. The maintenance procedure involves removing that connector, and over time it tends to wear out. The temperatures you indicate aren't that far out of line. I think a squirt of Deoxit and a good re-seating of the connector might do it, or the connectors may need replacing. It's the one at the passenger end of the PEM, on the bottom. Hard to get to.

If the assembly was just upgraded, have the service folks re-check the wiring. Mine was done wrong at some point in the past, and a number of fan-related issues were finally traced to a "wiring error".

Don't be sad. This can be fixed!
i will certainly check the plugs soon.

some further information: the alerts do not happen immediately after starting a ride. they start after everything has warmed up a bit, aprox. after 15-20 miles and then after i sucked heavy power from the battery occured by fast accelaration or high velocity.

and: the fault alert happens in standard/IR driving mode only but not when switched over to Max.Range driving mode. i remember that the alert happened in Max. Range mode also but it lasted much longer until alert and came more seldom.

i know that the cooling management in IR mode is different from MR mode. currents and cooling is limited in MR mode to save energy. so the fan starts blowing much later and IP1144 is shown much later then. right?

my unprofessional conclusion: most likely the alert is caused by the rear fan (it´s connectors?) and not by the liquid coolant system. but some experts say that the reason for 1144 is not distinct at all and may have the reason in the liquid circuit also (wrong pressure?). so i am afraid i will probably have to consider both...
But your liquid coolant is ONLY for the battery, it has nothing to do with code 1144. The motor and PEM are air cooled.
1144=Powertrain Problem
Unless you have other codes you haven't mentioned its not very prudent to look at the battery coolant
yes bart, a buddy is working on a much better connector version we want install in our cars. i think i will wait and install that solid plugs when available.

@ x.l.r.8: i agree to your logic thoughts but many others say that the roadster alert system is not logic at all and some strange alerts might be occured by a failure in the liquid coolant circuit. who knows...

thanx to everybody!
is there any serious reason against cutting the connectors and replace with insulation screw joints/lustre terminals?
Not sure exactly what you have in mind, but be careful to have a proper moisture seal, and insulation from anything that could come in contact with it. Screw terminals typically don't. There'd also be a hole in the PEM where the original connector was mounted, which could be an ingress point for water and/or dirt.

Also note that anything not conforming to Tesla's original equipment may cause the Service Centers to refuse to work on that part of the car, which would make the next annual service problematic.

If you find that the connector is indeed the problem, replacing both ends would be the best fix. That's what they did to mine, and it's been good for a few years now. In my case, they swapped the entire PEM for a refurbished one, but the board that the PEM-side connector is mounted on is apparently easy to remove and replace. They just can't (aren't allowed to) do that at the service centers.
They are pretty terrible connectors. They offer no cable support. They work for thick stranded copper wire but not multi strand like found in automotive applications. That’s before you even think about weatherproofing. What current is the fan pulling?
is there any serious reason against cutting the connectors and replace with insulation screw joints/lustre terminals?
The most serious reason I can think of is the current connector is water tight (mostly). Screw terminals are hard to protect from dirt and moisture. You also have to be able to quickly disconnonct/reconnect every time you clean the PEM.
1. the fan is equipped only with strands copper wires
2. this connection can easily be made waterproof
3. the fan pulls up to 25 A current maximum

so for me a heavy duty srew joint connection for those currents should always be superior to any delicate plug connection.
Off topic - but I think it just be a regional thing. In Germany I used those screw terminals all the time and it's how basically all electrical connections in construction are put together. Here in the US they are much harder to find and the ones around are usually small and cheap. I actually bring a bunch back with me every time I go to Germany.

In the end a screw clamp joint is always better than a plug for electrical connection (provided you take car of the mechanical side -protect from tension and moisture)
The problem with that analogy is that construction is a) solid so supports itself, b) static and does not move inside the wall cavity making the joint in a fixed environment, c) a single wire compressed allowing a good purchase of the terminal to wire, multi strand splays out reducing contact path.
Automotive connectors have 2 crimps on, one for support and one for conduction. A much better solution would be something like an xt60 or xt30. Pm me an address and I’ll send you one for free. There are plenty of other connectors around that are waterproof and will handle the power, just look at e-bikes.
Or split the cable and put 2, 2 pin IP68 connectors on so it shares the load between 2 plugs so you have a built in redundancy if a plug fails. Those plugs are $10 for 25 of them rated at 300w at 12v so you can easily play around.