Problem After Replacing Inverter Coolant Pump

Can you feel the pump vibrating or hear it humming when the car is in Ready mode? You need to establish that it is receiving power from the 12V and then go from there.

Edit: Ok, I see you can hear it. Is it vibrating?

 

Blockage somewhere in the plumbing or inverter cooling fins?

 

The replacement part might have been bad, or if there was a big enough air bubble in the pump it might not work. This is a nonpriming pump so, if, for instance, one just ran a tube from the inlet into a tub of water it would never get the water to run through it. That much of a bubble does seem like a bit of a long shot though.

You did bleed the system, yes?

It would not be hard to test the pump, but you would have to take the car partially apart again. Wear gloves. Block the two hoses that go to it with corks so little coolant is lost. Then put a longish hose on each end and prime it (fill the two hoses with plain water) then lower both ends (plugged with your fingers) into a bucket of water. Then have somebody turn on the car for a few seconds. Feel the pump so you know what "running" is like. If the pump is working it will move a lot of water in the bucket and you can rule out a failed pump. In fact if you are not holding the hoses the outlet one might shoot out of the bucket. The lack of cooling at the inverter will not be a problem for this short of a time. After that unhook the hoses on the pump and let all the water drain out. I would rinse it out with distilled water, just to avoid any possible reaction between your tap water and the coolant/components in the inverter. (Normally when these are installed they are straight from the factory and should be clean inside.) Then block the inlet (a third hand would be helpful at this point) and reattach the outlet hose. Finally, quickly reattach the inlet hose. Start the car again, does the pump feel like it is running? Then it probably is.

Note, while it would be easy to check "that it spins" with the pump not hooked up to anything, doing so might very well damage it.

If there is still no turbulence in the reservoir there might be a blockage elsewhere. The usual first step for such things is to drain as best one can (to capture the coolant) and then try to hose it out. There is likely a post describing how to do this somewhere in this forum.

Be sure to bleed the system again when you are done. And very carefully dry the bleed screw, so that if you see crystals on it later you will know that was from a leak and not drops you left there by accident.

 

For me this meant the replacement pump was bad. You can check by putting a meter on the connectors, it should read 14v DC. If it does then the pump is bad most likely...

 

Did it again recently. No turbulence. This time turns out I was "testing" for turbulence by hitting the "on button" twice (no brake pedal) (whatever that's called, aux 2?), and no turbulence. Turns out if I turned the car on fully, then it showed turbulence (i.e. yes brake pedal start). More volts, not running solely off a probably weak aux battery. Figured it out by detaching the hose leading to the inverter (

) and seeing it run out of that hose, but start to run less and less LOL. Just an FYI for followers...

 

It is called IG-ON.

If that is the case, there is something else going on as the pump should be running in IG-ON.

Maybe your battery was too far gone, but it would have to be really far gone not to be able to power that small pump.