All air vents blowing lukewarm air

[Digidick]

Recent purchase and my first issue.

Engine temp fine, water pipes coming to and from the
firewall are nice and hot but at best with temp set to max I can only get lukewarm air from the vents.

I’m new to this E89 lark so not sure what to check first.

 

[Pondy]

Check the little red/blue roller switch in the centre of the air vents on the dash is set to red (unless a you have a povvy spec 18i which doesn't have one).

 

[B21]

Could be the heater / blender unit going bad….

One failed on one of my cars ( a day after I sold it)…had the opposite issue, very hot air come what may..

 

[Digidick]

Could be the heater / blender unit going bad….

One failed on one of my cars ( a day after I sold it)…had the opposite issue, very hot air come what may..

Bet it’s not an easy fix is it?

 

[Digidick]

Check the little red/blue roller switch in the centre of the air vents on the dash is set to red (unless a you have a povvy spec 18i which doesn't have one).

Please! I’m new to E89’s but been around BMWs for years

 

[B21]

Check the little red/blue roller switch in the centre of the air vents on the dash is set to red (unless a you have a povvy spec 18i which doesn't have one).

Please! I’m new to E89’s but been around BMWs for years

Yes but Pondrew hasn’t…

 

[B21]

Could be the heater / blender unit going bad….

One failed on one of my cars ( a day after I sold it)…had the opposite issue, very hot air come what may..

Bet it’s not an easy fix is it?

Sadly no…usually a decent code reader diagnoses will show related error codes..

On the E89 you really need a decent code reader as many / most issues need an ECU / sensor / module diagnosis

 

[Pondy]

Check the little red/blue roller switch in the centre of the air vents on the dash is set to red (unless a you have a povvy spec 18i which doesn't have one).

Please! I’m new to E89’s but been around BMWs for years

In that case you should know the answer!

 

[Digidick]

Could be the heater / blender unit going bad….

One failed on one of my cars ( a day after I sold it)…had the opposite issue, very hot air come what may..

Bet it’s not an easy fix is it?

Sadly no…usually a decent code reader diagnoses will show related error codes..

On the E89 you really need a decent code reader as many / most issues need an ECU / sensor / module diagnosis

Only used BimmerLink so far and no faults.

 

[Digidick]

just read my post/question again

To make it clear I have cold air as well just not enough heat when I’m the higher temp settings.

 

[B21]

just read my post/question again

To make it clear I have cold air as well just not enough heat when I’m the higher temp settings.

It’s a very complex system given it appears to have some simple controls..

Not sure if bimmerlink would cut it…

If an ISTA / Protool class decoder shows no errors then I’m out of ideas..

 

[Digidick]

I do have a copy of ISTA somewhere, I’ll try and fire it up.

Thank you.

 

[B21]

I do have a copy of ISTA somewhere, I’ll try and fire it up.

Thank you.

Go for it

 

[Busterboo]

Engine temp fine, water pipes coming to and from the
firewall are nice and hot ...

Nevertheless, check engine coolant level. Engine cold, coolant cap off, is prong floating high?

 

[Busterboo]

Oh, good! TEN more photos of YELLOW cars. :crapparking:

 

[Digidick]

Engine temp fine, water pipes coming to and from the
firewall are nice and hot ...

Nevertheless, check engine coolant level. Engine cold, coolant cap off, is prong floating high?

Will be checking stuff over the weekend, car not being used currently. Will also check heater matrix, give it a flush perhaps?.

Interestingly it was at BMW specialist in May last year and they reported the issue but never got asked to look into it. Invoice says bled system twice but still blowing lukewarm.

Flaps were mentioned but I thought it would be hot in some areas and not others because of a failing one or is there a MAIN flap for all?

 

[jonnymac]

Check the little red/blue roller switch in the centre of the air vents on the dash is set to red (unless a you have a povvy spec 18i which doesn't have one).

That bloody thing caught me out for a few weeks

 

[Digidick]

Little update but still no answer.

Can't get my copy of ISTA working for some reason so...

Bled the system again and even flushed some water through the heater matrix and all clear.

The flow and return pipes are super hot so it looks like I've got the hot water getting into the car but something in the dash is stopping the hot air coming out the vents.

Would there be a 'Master' blend flap that controls hot/cold air as most peoples issues seem to be a mix of hot/cold on either driver or passenger sides?

Could the control panel itself cause this issue?

 

[B21]

The unit has quite complex systems as previously stated…see extract from BMW..

Yiu really need ISTA/Protool to make progress plus access to newTIS if you use Protool

 

[Digidick]

The unit has quite complex systems as previously stated…see extract from BMW..

Yiu really need ISTA/Protool to make progress plus access to newTIS if you use Protool

Thanks for that

I'm on it with ISTA!! - Trying to find someone local with it or another download to get it running again.

Is there an easy test I can run using ISTA to determine an issue?

Are there any particular flaps I can physically check that have the biggest affect on heat?