Replacing the thermal paste in a GS450H and some CAMRY inverter
Posted: Thu Apr 08, 2021 12:35 am
After having 6 or 7 inverters apart now this is a must for inverters that are more than 10 years old and i would do this for a inverter 6 or more years old as u can see in the second and third pics the paste has completely broken down
Removal guide from Lwerewolf
Replacement guide is, roughly:
-Disconnect 12v
-Disconnect battery service plug
-Wait at least 10 min
-Remove the inverter's battery and AC connector cover
-Measure voltage at both terminals there with a voltmeter - should be 0v, can be up to 750v if the smoothing/filtering/DC link/whatever you want to call them capacitors haven't discharged - there are bleeder resistors in place for this to happen, and it should happen way faster than 10 minutes, but don't fool around with this.
-Disconnect everything from the inverter - MG1 & MG2 connectors, battery & AC connectors, wire harness connector, water hoses (make sure you protect all connectors from coolant drops/spillage/spray/etc - especially if you decide not to drain the system beforehand).
-Replace the inverter
-Install water hoses, MG/Battery/AC/Harness connectors
-Install battery service plug
-Connect 12v
-Initialize car (windows & sunroof up & down, all doors open & close, transmission learn, etc) - not really necessary
-Bleed coolant loop (inverter water pump can be run with techstream, alternatively it runs 20sec after car goes in "ready" mode)
That's it, officially
Thanks Lwerewolf u help so many people
What else u will need
At lesst 20g of industral long life thermal paste
500lm of toyota coolant(if u dont drain the coolant just remove and temp plug hoses)
1/4 drive 10mm socket ratchet and extension
4mm and a 6mm allen key(i had a 1/4 drive one)
Pliers for the gose clamps (i use 45 degree long nose long handle)
UTV sealant
Now strip the lower half of the inverter off by
First removing 2x 10mm bolts on the coolant conection side holding the black plate on
Then pry the black plastic plug out ( dont damage this to much u need it)
Undo the 2x 10mm u see in the hole
Now undo the 4mm allen bolts holding the lower half on
And very cearfully pry the base off (note the 2x dowels i start at the end with the coolant connections at the dowel) remove base
Remove the board in 4th pic with 4x screws and 6x plugs
Now undo the 4x 10mm in the side that hold the two motor/gen cables
Now on the inside remove the 6x 10mm bolts (marked with red arrows in pic )holding the motor/gen bus bar connectors onto the IGBTs and pry the connector and housing off the side of the inverter
Now remove the 12x6mm allen screws holding the IGBTs to the inverter body
Now remove the IGTBs and soldered on board (this is the only bit u need to re paste in inverter)
Clean the inverter and the IGBTs and reaplay a very thin layer of thermal paste to the IGBTs only (note i found if i left the paste in hot water for awhile it was much easier to apply)
Reasamble the lower half of the inverter
Removal guide from Lwerewolf
Replacement guide is, roughly:
-Disconnect 12v
-Disconnect battery service plug
-Wait at least 10 min
-Remove the inverter's battery and AC connector cover
-Measure voltage at both terminals there with a voltmeter - should be 0v, can be up to 750v if the smoothing/filtering/DC link/whatever you want to call them capacitors haven't discharged - there are bleeder resistors in place for this to happen, and it should happen way faster than 10 minutes, but don't fool around with this.
-Disconnect everything from the inverter - MG1 & MG2 connectors, battery & AC connectors, wire harness connector, water hoses (make sure you protect all connectors from coolant drops/spillage/spray/etc - especially if you decide not to drain the system beforehand).
-Replace the inverter
-Install water hoses, MG/Battery/AC/Harness connectors
-Install battery service plug
-Connect 12v
-Initialize car (windows & sunroof up & down, all doors open & close, transmission learn, etc) - not really necessary
-Bleed coolant loop (inverter water pump can be run with techstream, alternatively it runs 20sec after car goes in "ready" mode)
That's it, officially
Thanks Lwerewolf u help so many people
What else u will need
At lesst 20g of industral long life thermal paste
500lm of toyota coolant(if u dont drain the coolant just remove and temp plug hoses)
1/4 drive 10mm socket ratchet and extension
4mm and a 6mm allen key(i had a 1/4 drive one)
Pliers for the gose clamps (i use 45 degree long nose long handle)
UTV sealant
Now strip the lower half of the inverter off by
First removing 2x 10mm bolts on the coolant conection side holding the black plate on
Then pry the black plastic plug out ( dont damage this to much u need it)
Undo the 2x 10mm u see in the hole
Now undo the 4mm allen bolts holding the lower half on
And very cearfully pry the base off (note the 2x dowels i start at the end with the coolant connections at the dowel) remove base
Remove the board in 4th pic with 4x screws and 6x plugs
Now undo the 4x 10mm in the side that hold the two motor/gen cables
Now on the inside remove the 6x 10mm bolts (marked with red arrows in pic )holding the motor/gen bus bar connectors onto the IGBTs and pry the connector and housing off the side of the inverter
Now remove the 12x6mm allen screws holding the IGBTs to the inverter body
Now remove the IGTBs and soldered on board (this is the only bit u need to re paste in inverter)
Clean the inverter and the IGBTs and reaplay a very thin layer of thermal paste to the IGBTs only (note i found if i left the paste in hot water for awhile it was much easier to apply)
Reasamble the lower half of the inverter