heater support pump stuck on

[Racerxr]

manual trans 2015 golf tdi se got a few weeks ago wrecked all i had to do was replace bumper cover and radiators main aux and ac condenser and support got it all done vacuum filled coolant. fired it up test drove 5-10 miles everything was great! next morning battery was dead put new battery in as soon as i hook the cables up it sparks, the heater support pump? turns on and runs til the battery is dead. cold car no key in ignition

I'm assuming its the heater support pump from what i can tell. aux pump is between radiator and engine the pump that is on is between engine and firewall on passenger side

this is my first VW and first car with electric cooling pumps so what do I check is there a relay could really use some help here thanks guys

 

[740GLE]

You should have some codes for that pump, might be the relay got shorted out. A scan will tell you what relay it is then it'd be a matter of find it under the hood.

Or you could test all the relays see which ones failed shut.

 

[adjat84th]

Definitely scan for codes if you haven't already.
The heater support pump should only run when the main (Timing belt driven) water pump is in warmup mode and the shroud covers that impeller to aid in marginally faster warmup of the coolant. The aux heater pump continues to push coolant through the block/head, EGR, and heater core to get heat faster to the cabin.
Is the main water pump solenoid connected? I could see how if that failed in the "closed" mode, your aux pump would want to stay running...but not with the car off.

 

[740GLE]

IMO i think he's talking about the A2W intercooler pump, the one that needs the connector removed to pull the oil filter.

 

[adjat84th]

the pump that is on is between engine and firewall on passenger side

Either way, a scan is on order to see what's going on.

 

[740GLE]

agreed