electric water pump can anyone confirm

[8YA335TDI1STED]

hi all having probs with my ac fan not running and also noticed my electric water pump dosent always run .

question is ? should this pump be running constantly or does it need to be at full temp before it kicks in


Ive looked at elsawin and it says it should be on when ignition is turned on ( which it does ) but it doesnt seem to be on after a blast of the heavy throttleage maximus type ??

 

[jojo]

Electric waterpump? It runs of the crank/cambelt on an S3.

 

[rossbrownlee]

Jojo he is referring to the electric run-on coolant pump that runs for a while after the ignition is switched off, at the front of the bay just towards the front from the alternator.

 

[jojo]

Jojo he is referring to the electric run-on coolant pump that runs for a while after the ignition is switched off, at the front of the bay just towards the front from the alternator.

In that case, it only runs when the ignition is switched off, even if you start the car to move it 10 yards, the electric pump will run for like 5 minutes once you switch the ignition off.

 

[aragorn]

On the S4 the electric pump has its own coolant switch, so it will only run if the coolant is over a certain temp when turning the ignition off (100c or somthing on the S4)

IIRC the pump, and all the fans run thru a controller, which on the S4 is bolted to one of the inner wings. I'm pretty sure i've read the S3 uses the same controller.

If your AC fans wont run, and the afterrun is acting odd, i'd be looking at the controller or its fuses as a first instance.

 

[8YA335TDI1STED]

Jojo he is referring to the electric run-on coolant pump that runs for a while after the ignition is switched off, at the front of the bay just towards the front from the alternator.

thats the very one Ross , its fitted to the left hand side top of the radiator when looking into the engine bay from front, its job is to cool the turbo after engine shut down , ive heard mine running when i first bought the car it always ran , but then i changed my stat and coolant fluid and now it dosent run after a blast ? asfik it is controled by the fan module which in turn would be controlled by the dual temp sensor , Im just trying to find out how it should behave in normal operation ? ie is it on all the time / only at max temp/ always when engine is switched off ????

 

[aragorn]

As above, there should be a second switch for it.

The S4 has two sensors in the main coolant gallery on the rear of the head, one for the CTS (which does ECU and dash) and one for the Afterrun.

Afterrun switch is a two pin thing, and its quite common for S4 folks to swap out the sensor for a lower rated one, so it cuts in at a lower temperature/more often.

The controller is the same part number on the S4 and S3 afaik. The afterrun only engages when the ignition is switched off, and the coolant temp exceeds the rating of the switch, for a maximum of 10 minutes.

If your AC fans arent working, then the controller might be broken.

 

[8YA335TDI1STED]

As above, there should be a second switch for it.

The S4 has two sensors in the main coolant gallery on the rear of the head, one for the CTS (which does ECU and dash) and one for the Afterrun.

Afterrun switch is a two pin thing, and its quite common for S4 folks to swap out the sensor for a lower rated one, so it cuts in at a lower temperature/more often.

The controller is the same part number on the S4 and S3 afaik. The afterrun only engages when the ignition is switched off, and the coolant temp exceeds the rating of the switch, for a maximum of 10 minutes.

If your AC fans arent working, then the controller might be broken.

does the dual temp sensor have any effect on the afterun or ac control ? thinking change this first and investigate relevant connectors b4 buying a new fan module

 

[aragorn]

No. The dual coolant sensor only provides a signal to the dash and the ECU.

Check the big fuses for the fan module. There are two or three iirc.

 

[8YA335TDI1STED]

No. The dual coolant sensor only provides a signal to the dash and the ECU.

Check the big fuses for the fan module. There are two or three iirc.

update, changed the the three fuses on top of battery with new ones , also bought some industrial electrical contact cleaner from cef, ( be warned dont spray this stuff on your fingers it almost froze my fingers off lol ) anyway razzed the cleaner into where the fuses fit and replaced them , then removed the battery tray to get to the fan module , same again dismantled this and razzed it with the cleaner , also did the same with the dual temp sensor ( seems original one its black in col ) all this work had no affect on the rad fans so opted to recharge the coolant assuming the high pressure coolant switch was doing its job fans now cut in ac working , but im still very suss about the electric run on pump , I want to make absolutely sure this device is working as it should or i might end up needing a new turbo , could u tell me where the temp sensor which controls this pump for the S3 is fitted Aragorn ? thanks for the help so far guys :icon_thumright:

 

[S3Zek]

Sorry to bring up an old post but did you get this sorted? Mines just decided to do the same. I know the pump works as I've tested it and I have power at the small 10 amp fuse in the car, but nothing at the pump after I turn the ignition off. Is there a sencer I can change or is the control for these a common prob? Cheers

 

[S3Zek]

Also the air con pump won't stay engaged, try's then stops straight away, dose this over and over.

 

[S3Zek]

Also the fuses on top of the battery all seem ok to?

 

[S3_Olly]

Hi iv got a similar issue as only one of my fans ever works even if it's red hot and iv taken it out for a good spin.
Is this normal of should they both spin and what are possible effects / solutions?

Thanks

 

[S3Zek]

Pumps just started working again.....not sure why? as after poking about in the bay yesterday it still wasn't working, went out just after I did the last post on here and again still nothing...moved the car over in my yard 10 minutes ago and now working like it never stoped......am I right in thinking that it's prob the controller?

 

[Flubster]

I have never heard this pump, infact didn't even know it had one Guess mines not working then, anyone got an image of where the pump is? Incase its just stuck and needs some gentle persuasion? From reading some threads I've checked the fuses on top near the battery and they all appear fine!

Dave

 

[<tuffty/>]

I have never heard this pump, infact didn't even know it had one Guess mines not working then, anyone got an image of where the pump is? Incase its just stuck and needs some gentle persuasion? From reading some threads I've checked the fuses on top near the battery and they all appear fine!

Dave

Just above the left hand fan as you look in the engine bay...

<tuffty/>