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

PEM FAN Connector pin identification

jfischer

Member
Feb 6, 2014
186
246
Houston
Anybody happen to have the pin-out labels for Rear Harness Connector 34 ( RHC34) as shown below. This is the PEM connector that attaches to the PEM FAN connector on the bottom of the PEM istelf.

I have the pins but not what each line I used for. I'm guessing PIN 1 is 12v Positive and 2 is 12v negative since these are the two pins that usually get toasted. I have the pins and the cable colors, just need to know what each of the 4 cables is used for.

upload_2020-6-20_14-33-56.png


I just need to descriptions to the right, if anyone has them.

Thanks!!!
 

jfischer

Member
Feb 6, 2014
186
246
Houston
weird when I look at the schematics, the wire colors differ as well... I must have a different diagram then you do @MLAUTO .

upload_2020-6-20_16-47-58.png


Looks Like Pins 1 and 3 go to some Motor Cooling fan and pins 2 and 4 go to PEM cooling fan.
Colors are not what shows up under PEM.

typical....
 

Attachments

  • upload_2020-6-20_15-31-14.png
    upload_2020-6-20_15-31-14.png
    40.2 KB · Views: 36
  • Like
Reactions: drewski

jfischer

Member
Feb 6, 2014
186
246
Houston
Any suggestion from testing it at the RHC34 connector after it’s removed from PEM?
I have to rewire the connector anyway so was just going to feed 12v to pins 2 and 4 and see if fan blows.. Ohm test as well? Just looking for suggestions before I actually have to crawl under car and test from there..
 

gregd

Active Member
Dec 31, 2014
2,531
1,768
CM98
Doesn't this depend on whether the dual-fan upgrade has been done. If so, then aren't the two fans wired in parallel, and fed to the single motor? Or, is this for the 1.5 model?
 

jfischer

Member
Feb 6, 2014
186
246
Houston
Doesn't this depend on whether the dual-fan upgrade has been done. If so, then aren't the two fans wired in parallel, and fed to the single motor? Or, is this for the 1.5 model?

On the 1.5 there were TWO motors, One MOTOR FAN and one PEM FAN. On the 2.0/2.5 there is one motor driving both fans.

So not sure which pins are actually in use. I know the fan is 12V based on the SPAL fan specs and based on the connector damage it looks like its using the MOTOR pins ( #1 and #3) instead of PEM Cooling fan pins (#2 and #4)

I'm going to feed the fan wires 12V and see if the fan blows air as a test while I have the PEM pulled.

I replaced the connector on the bottom of the PEM as well, job wasn't too hard, just need to be organized with all the board placements and screw locations. Lots of pics showing what was disconnected and how it all goes back together... but doable with some patience and solder skills. I'll post a walk thru of the process later this week if anyone is interested.
 
  • Informative
Reactions: dhrivnak

jfischer

Member
Feb 6, 2014
186
246
Houston
rd/bk--motor fan +
rd/yl--pem fan +
br/rd--motor fan -
br/yl--pem fan -

You dont have the wiring diagram?

The "Roadster Circuits - 2010 LHD PDF" I have shows different color wires, Mine shows BLACK wires but the rear harness and your note shows brown wires, which is exactly what color my harness has.




Based on the connector damage it looks like pin #1 is in use... maybe some of #2 as well as it shows slight damage

01B4AE10-0B2F-40BA-BA4A-D9EEFF965E7A.jpeg

A2C8A4F2-BE4B-4D75-B1A3-074F1E6B3206.jpeg
 
Last edited:

PV-EV

Member
Jun 3, 2011
416
257
Alaska
Both connectors are toast. You need to replace the right angle Molex connector inside the PEM. I made a temporary fix once by cleaning up the pins from the PEM and soldering on a pigtail that’s mated with the connector to the fans. Eventually opened the PEM and replaced the connector for a permanent fix.
 
  • Informative
Reactions: dhrivnak

jfischer

Member
Feb 6, 2014
186
246
Houston
Both connectors are toast. You need to replace the right angle Molex connector inside the PEM. I made a temporary fix once by cleaning up the pins from the PEM and soldering on a pigtail that’s mated with the connector to the fans. Eventually opened the PEM and replaced the connector for a permanent fix.

i actually did just that. Took a few hours to pull and open the pem. Get the CIC board out and replace the connector on the pem.

Was a good learning experience. I can probably document it better if someone is looking to do it. Have lots of pics as I broke it down and put it back. Just takes some time and careful inventory of what screws and bonds go where.

many thanks to @CM_007 for the step by step walk-thru of how to do it and my many many questions...

also to @MLAUTO for the pinouts for the connector which allowed me to test the fan with the PEM out.

let me know if anyone wants to try this and ill try to put something descriptive together

7335C45E-1F25-4C9A-AC8D-203E52EBEA24.jpeg
E638F0DB-4498-4326-9D84-FC0D3F1FFA94.jpeg
6E71DD9C-1307-4034-8A43-B69E796F0420.jpeg
51BD2676-3DD8-4FF8-90C6-DFB06314C505.jpeg
8351D2EC-29C4-4CE3-9587-C77AEF316CA5.jpeg
DC930CB3-5B13-46AB-907C-9ACD4E720900.jpeg
AB57E192-5A94-4222-BCE1-A23E07B8CD09.jpeg
 
Last edited:

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top