No heat from heater

Find out more about the BMW 1 Series E81, E82, E87, E88.
Manufactured from 2004 to 2013

Moderators: babybmwadmin, Producethis, marco_polo, Rich196, Lambster

Post Reply
MrMorGz
Junior Member
Junior Member
Posts: 1
Joined: Thu May 16, 2019 7:31 pm

No heat from heater

Post by MrMorGz » Thu May 16, 2019 8:17 pm

Hey guys, long time lurker but first time poster. 2 weeks ago I acquired my 125i e82 and love it. After about 2 days I'd noticed that the heater doesn't draw heat to the cabin, fans work and aircon works. Initally I though the car was overheating as my e46 loses heat the overheated. I checked the secret obc and the temps are fine. over the course of 2 weeks owning it heat it slowly returned, now if I put the heaters to 28c I get luke warm heat for about 5 minutes before it goes back to cool ambient air. I did some basic checks, the cabin filter is clear and the coolant is bled correctly but still no change. I borrowed my friends obd reader and was looking through that, engine temps are fine and no error codes. Something didn't make sense though, the ambient air temp sensor on the obd reads as 32c, even though it's 13c outside, AND the obc on the dash reads as 13c. If the sensor was faulty then why does the obc on the dash read correctly? and if it were the heater matrix or something behind the dash then why do I get some heat for a couple minutes? I'm a little stumped here, wondered if you guys could shine some light. The car is covered by warranty, but if it's a cheap simple fix then I'd rather do it myself instead of being without the car for a couple days. Is there a cabin sensor that could be reading wrong? If so how I would I check?


Thanks for any help :)

User avatar
marco_polo
Too Much Time To Waste Member
Too Much Time To Waste Member
Posts: 54164
Joined: Tue Apr 06, 2010 9:40 am
Location: Omnipresent Post Whore

Re: No heat from heater

Post by marco_polo » Thu May 16, 2019 8:22 pm

Cabin temp sensor makes sense.
Silver F21 M135i - ManBox - HK - Adaptive + Eibach Pro's - BBS CH-R's - BMWP Drexler LSD - M4 LCA's

Please help the Mod's by using the report [ ! ] button where appropriate

User avatar
Nottsknots
Too Much Time To Waste Member
Too Much Time To Waste Member
Posts: 3125
Joined: Sat Jun 29, 2013 8:35 pm

Re: No heat from heater

Post by Nottsknots » Thu May 16, 2019 8:47 pm

There are a fair few sensors
- external iar temp
- engine intake
- footwell
- dash
(and maybe more if you have split cabin climate control).

Chances are its one of the many.

Could also be the matrix clogging - flow can sometimes get through before it blocks again.

Personally, if its under warranty, I’d take it back and let them diagnose it, rather than spend the hours on it yourself; hours without the car are better than hours without the car AND getting frustrated.
E87 118d, stock, plus PDC control unit drain, Parrot, debadged, Mothercare baby shades (but no babies), and occassionally a good layer of wax. Instantly forgettable, and thats the way I like it.

Not long now until the end of May...

Dave2032
Knowledgeable Member
Knowledgeable Member
Posts: 82
Joined: Thu May 31, 2018 8:41 pm

Re: No heat from heater

Post by Dave2032 » Thu May 16, 2019 10:46 pm

I’d put money on it being a blocked heater matrix.

Take off both water hoses where they go through the bulkhead, attach a garden hose to the matrix exit hose and blast it backward out the matrix inlet.


Sent from my iPhone using Tapatalk

Pathaleon
Junior Member
Junior Member
Posts: 15
Joined: Tue Nov 13, 2018 5:34 pm

Re: No heat from heater

Post by Pathaleon » Fri May 24, 2019 6:11 pm

Have you checked your water pump is working properly?

Post Reply

Return to “E81, E82, E87, E88 (2004-2013)”