00A6D1 Code

[MaximusB]

Decided to run a diagnostic with Carly last night and I got the following fault code came up:

00A6D1
"Short circuit to positive or open circuit - Additional water pump."

Did search in this forum and online but can't seem to find out too much information about it. It appears it is an AUX water pump that is throwing the fault code but the issue seems to only affect 3 series, not the m3.

Anyone had this issue before? Is it something easy to replace? Luckily I'm bringing my car into an Indy shop for oil change today, so I'll probably ask them to scan it again and check in with them.

[deansbimmer]

Contrary to popular belief, the M3 does in fact have an aux water pump as a component of the HVAC system. It is located on the driver side frame rail near the strut tower. PN 64118369806. Before buying parts I would have the code checked with BMW software to be sure that is the correct component for the code. And yes, it is easy to replace.

[MaximusB]

Originally Posted by deansbimmer

Contrary to popular belief, the M3 does in fact have an aux water pump as a component of the HVAC system. It is located on the driver side frame rail near the strut tower. PN 64118369806. Before buying parts I would have the code checked with BMW software to be sure that is the correct component for the code. And yes, it is easy to replace.

Awesome! Thanks for the quick response. One thing I am not too clear about is the function of this pump. I read that it is to circulate coolant around after the car is off?

I'll definitely have the shop scan it again today to confirm, if it is something easy/cheap to replace then I won't even bother going through with the dealer or my extended warranty.

[deansbimmer]

Yes as part of the HVAC system it circulates coolant from a warm engine block through the heater core to maintain heater output after you turn the engine off. Dealer retail on the pump is about $200. I have dozens of good used used ones I sell for $30 each. Not worth the warranty hassle IMO.

[Helmsman]

Maximus, just double checked my Carly Garage and I did have the same code at some point. The way I remember it, it came in conjunction with a battery drain (ignition on while fixing something..). I cleared it a few times while charging the battery and it never came back. FWIW.

Cheers

[MaximusB]

Originally Posted by deansbimmer

Yes as part of the HVAC system it circulates coolant from a warm engine block through the heater core to maintain heater output after you turn the engine off. Dealer retail on the pump is about $200. I have dozens of good used used ones I sell for $30 each. Not worth the warranty hassle IMO.

Agreed, especially in my case where I paid $3500 for 4 years extended warranty and I get all that money back after 4 years if I don't make any claims. Basically anything under $3500 I'm just going to pay out of pocket.

Originally Posted by Helmsman

Maximus, just double checked my Carly Garage and I did have the same code at some point. The way I remember it, it came in conjunction with a battery drain (ignition on while fixing something..). I cleared it a few times while charging the battery and it never came back. FWIW.

Cheers

Awesome, thanks for the help! I'll see what the shop say when I take it in for an oil change later this afternoon. I might just try your method tonight when I get home.

[MaximusB]

So the Indy shop scanned it and they said it is a soft fault (whatever that means) and it is most likely battery related. Interestingly they didn't measure the voltage on the battery.

[deansbimmer]

Soft faults are faults that are stored in a module as having occurred previously, but are not currently present at the time of scanning. Those are the ones we clear and see if they come back later after a few drive cycles. If they do then we replace the part.

[Mdriv3r]

Originally Posted by deansbimmer

Yes as part of the HVAC system it circulates coolant from a warm engine block through the heater core to maintain heater output after you turn the engine off. Dealer retail on the pump is about $200. I have dozens of good used used ones I sell for $30 each. Not worth the warranty hassle IMO.

Originally Posted by deansbimmer

Yes as part of the HVAC system it circulates coolant from a warm engine block through the heater core to maintain heater output after you turn the engine off. Dealer retail on the pump is about $200. I have dozens of good used used ones I sell for $30 each. Not worth the warranty hassle IMO.

You still have these for sale for e92 M3?

[Xgelato]

Originally Posted by deansbimmer

Yes as part of the HVAC system it circulates coolant from a warm engine block through the heater core to maintain heater output after you turn the engine off. Dealer retail on the pump is about $200. I have dozens of good used used ones I sell for $30 each. Not worth the warranty hassle IMO.

Hey deansbimmer. I'm in need of one of this. How do I get in contact with you?

[Helmsman]

Originally Posted by deansbimmer

Contrary to popular belief, the M3 does in fact have an aux water pump as a component of the HVAC system. It is located on the driver side frame rail near the strut tower. PN 64118369806. Before buying parts I would have the code checked with BMW software to be sure that is the correct component for the code. And yes, it is easy to replace.

Hey Deansbimmer, would you by any chance have experiences from a failing aux pump causing DCT over heat?

My aux pump has been out for some time. In parallel I've got DCT over heating code now and then. Reading into this a bit more I realize the aux pump also help providing coolant to the DCT (below 95degC when the DCT coolant exchanger is used, where after switching to the air heat exchanger).

Any thoughts on this?

Cheers

Doc I'm refering to: https://www.m3post.com/forums/attach...4&d=1317583307

[THRSTYM3]

Originally Posted by deansbimmer

Yes as part of the HVAC system it circulates coolant from a warm engine block through the heater core to maintain heater output after you turn the engine off. Dealer retail on the pump is about $200. I have dozens of good used used ones I sell for $30 each. Not worth the warranty hassle IMO.

Do you still have of these aux water pumps for sale?
does this effect the DCT cooling? started getting A6D1 additional water pump code on bimmerlink.
What is the consensus of the code? is it worth replacing?

[Helmsman]

Originally Posted by THRSTYM3

Do you still have of these aux water pumps for sale?
does this effect the DCT cooling? started getting A6D1 additional water pump code on bimmerlink.
What is the consensus of the code? is it worth replacing?

The pump both help pre heat the DCT as the coolant comes up to temp quicker as well as "stabilize" DCT fluid once much above coolant temp (i.e. 78C isch). If pre LCi car it also circulate coolant when parking heat in use. On top you get rid of the freaking code...:-).
Its $250 and 30min tops to replace so I'd say yes worth it.

[THRSTYM3]

thank you

[jrlee53]

Originally Posted by Helmsman

The pump both help pre heat the DCT as the coolant comes up to temp quicker as well as "stabilize" DCT fluid once much above coolant temp (i.e. 78C isch). If pre LCi car it also circulate coolant when parking heat in use. On top you get rid of the freaking code...:-).
Its $250 and 30min tops to replace so I'd say yes worth it.

I'm looking to do this too as mine failed and noticing engine temps rise and no heat when standing idle. Ive already changed the water pump and my indy shop didn't think the the sensor is bad, but also didn't think the aux pump was the cause, though it makes sense if it is given my issues.

Do you need to remove and reinstall the clamps from the hose at all or just need to pull away from the pump and reinsert the hose? I don't have the tool needed to release those self adjusting clamps. First time doing this so any info is appreciated.

[Helmsman]

Originally Posted by jrlee53

I'm looking to do this too as mine failed and noticing engine temps rise and no heat when standing idle. Ive already changed the water pump and my indy shop didn't think the the sensor is bad, but also didn't think the aux pump was the cause, though it makes sense if it is given my issues.

Do you need to remove and reinstall the clamps from the hose at all or just need to pull away from the pump and reinsert the hose? I don't have the tool needed to release those self adjusting clamps. First time doing this so any info is appreciated.

The way I remember it I took of the clamps and if so without any special tools. I did not buy any new clamps but reused. The only "special" needed is a couple of cheap "hose pliers" (like below) in order to keep the coolant in place. As the pump is not even bolted it was a very straight forward job.

If the pump is broken (and eventually I think they all go because of fluid/rost), you will get the A6D1 code everytime the pump wants to start (after clearing the code, comes back). If you don't get this code I would guess there is another issue.

https://www.amazon.se/Slangkl%C3%A4m...E&gad_source=1

[jrlee53]

Originally Posted by Helmsman

The way I remember it I took of the clamps and if so without any special tools. I did not buy any new clamps but reused. The only "special" needed is a couple of cheap "hose pliers" (like below) in order to keep the coolant in place. As the pump is not even bolted it was a very straight forward job.

If the pump is broken (and eventually I think they all go because of fluid/rost), you will get the A6D1 code everytime the pump wants to start (after clearing the code, comes back). If you don't get this code I would guess there is another issue.

https://www.amazon.se/Slangkl%C3%A4m...E&gad_source=1

Thanks, was looking to get those hose pliers as well so I don't need to do another coolant flush again. I'll give it a try and hopefully don't break those clamps in the process. Mine's definitely the pump as the code keeps coming back. I'm also at 160k miles so not surprising. Hopefully changing the pump will alleviate my weird temp issues.

[Helmsman]

Originally Posted by jrlee53

Thanks, was looking to get those hose pliers as well so I don't need to do another coolant flush again. I'll give it a try and hopefully don't break those clamps in the process. Mine's definitely the pump as the code keeps coming back. I'm also at 160k miles so not surprising. Hopefully changing the pump will alleviate my weird temp issues.

Ps. You will lose a little bit of coolant even with the pliers. Air the system by running engine with full heat on and top up.