Warning Light after repair

Hi Guys,

I had my petrol engine water pump replaced yesterday at a local mechanic, as it was leaking coolant. As far as I know the hybrid water pump is fine.
After about 15-20 minutes of driving, I get a red exclamation mark flash on the dash, followed by "Problem" on the MFD. It happens once, then a few minutes later, 3 more times within a couple of minutes for about 5 seconds at a time. I stopped to try and figure out what it was, couldn't, then continued on and didn't encounter the error again.

This morning while driving to work, it happened again after about 20 minutes, but this time after the "problem" it gave me an actual error symbol in the left corner of the MFD. It is the symbol for "high coolant temperature".


I had them install an off-market water pump as they assured me it was just as good quality, and came with the same warranties as a toyota pump, and was overall $150 cheaper.
Could this be a faulty pump, or have they installed it incorrectly?

Thanks guys

 

Right okay, thanks for that.

I am taking it in tomorrow to get them to look at it, is there anything I should tell them that they need to do?

This was why I've been using Toyota since I got the car, I've felt that local mechanics just won't be as well versed in the minutiae of the car, and I've been willing to pay a huge premium at Toyota for piece of mind.
Toyota quoted me $550 for the water pump replacement, and the local dealer did it for $250 with an off-market pump, so I couldn't really justify that.