What is the MECS pump?

 

Motor Electronics Coolant Pump that cools the transmission motors and DC/DC converter.

GaryG

 

Gary,
Is it located near the front of the engine compartment? The other evening I hear a sort of humming noise near the front of the car, which I noticed when stopped at a light and the ICE off. I'm wondering if it is starting to go, although I've only got 60K on my 2008.

 

In EV, two electric pumps run under the radiator. The small heater pump circulates engine coolant to he heater core when the belt driven pump stops when in EV. The MECP is the larger pump and runs when the key is in the On position. The engine does not need to be started to check for MECP noise. No noise, the pump is bad or power to the pump is cut. I've talk to my hybrid tech and he says the wire connection to the pump often short and he has fixed them, but it doesn't last long. I've never had a bad MECP, but if I do, I'll change either pump myself.

GaryG

 

Thanks for the information. Since I hear a noise, maybe everything is OK, but this is the first time in 5 years that I've noticed that noise with the ICE off. Oh well, I'm still on my extended warranty...