Intermittent after run pump

[vanilla_ice]

Hi,

The pump not running after every journey. It runs fine when connected directly to battery. Appears to have a low voltage when connector is tested with multimeter. How should I go about testing further? I've purchased a new pump but no change.

Does anyone have any pictures or diagrams of the wiring that feeds the pump?

Thanks.

 

[s3mad_dude]

Hi, a while back I noticed my pump was intermittent (more often it didn’t run) and I mentioned it to the garage when the car was in for some work and they replaced it. It now runs every time. I’m not saying what mine does is normal but that’s what it does, so just sharing my experience.

Did you use a Bosch OEM part?

 

[vanilla_ice]

Thanks @s3mad_dude

The pump that's fitted is a Bosch, fitted about six years ago. Runs at a good speed when wired directly off the battery.

I recently purchased another Bosch pump. Went for a short drive and when I got back I plugged the electrical connection on to the new pump (while in my hand) and it didn't run at all.

I have also replaced the fuse box on top of the battery with a used genuine part. My original hard got warm at some point. This one appears to be in good condition.

I wondered if it could be a dodgy relay?? Just not sure the relevant relay would be...

 

[vanilla_ice]

I found this:

Does anyone know where on the car I'd find relay "13"? Under steering wheel?

 

[s3mad_dude]

Definitely worth checking the relay but not a clue where to look - sorry. I guess you’ll just have to fumble around with a torch! Keep us posted though

 

[desertstorm]

The 13 way relay plate is located above the accelerator / brake pedal. You need to remove the trim panel under the steering wheel. On my 2001 225 MK1 TT the after run pump is controlled by the fan control relay. This is located under the battery bolted to the chassis rail by the radiator.

 

[vanilla_ice]

The 13 way relay plate is located above the accelerator / brake pedal. You need to remove the trim panel under the steering wheel. On my 2001 225 MK1 TT the after run pump is controlled by the fan control relay. This is located under the battery bolted to the chassis rail by the radiator.

Thank you for that. I should have said that the fan controller you mention has already been replaced (used part). The fans appeared to run correctly both before and after changing that. The after run pump seemed better after changing the fuse box on top of the battery.

(I had wondered if some 'gremlins' in that 'area' were interfering with my AC. Clutch engages, pump spins, no leaks but no cold air blows. Was advised to replace the pump, but I'm putting that off for now).

I found this workshop manual and hoped someone had the relay model or part number. The manual refers to J151, but havent been able to identify the correct part. Assuming they aren' t too expensive, I'd like to source one before I remove the trim panel.

 

[desertstorm]

What year is your car?

 

[vanilla_ice]

2001 AMK

 

[desertstorm]

On the AMK it's definitely a timer relay that controls the after run pump. If your radiator fan is working then the pump runs off the same 30A feed . The other feed to the relay is a switched live used by many other circuits so if that was faulty you would have many other issues.
The relay is located in the relay plate under the steering column. I believe it's probably marked 411.
Like this relay.

Audi A4 S4 B6 8E 8H 2004 Other relay 1J0959485A KLI31562 | eBay

<p dir="ltr" style="margin-top:0; margin-bottom:0;">Audi A4 S4 B6 8E 8H 2004 Other relay 1J0959485A KLI31562.</p> <br> <p dir="ltr" style="margin-top:0; margin-bottom:0;">BRAND NEW GENUINE </p>

www.ebay.co.uk

 

[vanilla_ice]

Many thanks @desertstorm

So if I'm not experiencing 'many other issues', you don't think replacing the '411' relay is likely to help with the pump? Or have I misunderstood you?

I have a parasitic drain that I haven't been able to find the source of...

 

[desertstorm]

Many thanks @desertstorm

So if I'm not experiencing 'many other issues', you don't think replacing the '411' relay is likely to help with the pump? Or have I misunderstood you?

I have a parasitic drain that I haven't been able to find the source of...

Think you have misunderstood me, If you have no other issues then there is a good chance that the 411 relay has an issue. I would be tempted to pull it and check the contacts are good. You can easily pull the plastic cap off and have a look inside the relay and see if you can see anything.