Aux Heater problem

[Dessie]

I realise this has been covered before but I am looking for a bit of advice.

I was in the smug zone last year,setting my timer and coming out to a nice warm frost free car in the morning.

I set it last week and again last night and was rather disappointed to find nothing had happened either morning. The heater unit seems to be working ok as I had I had hot air within a couple mins of starting the car. When I got to work the little exhaust underneath was pumping hot fumes and was nice and hot itself. It runs on for a little while after I have switched the engine off.

I moved the car tonight to let my son out of the drive and there was steam /condensation coming out of the the exhaust almost immediately.

Can anyone suggest why the heater will not work without the engine running when it has in the past, both on timer and direct mode.

Thanks

Derek

[CondorX5]

Possibly battery dropping too low in the cold - heater will not come on if the voltage drops below a certain level.  Maybe worth a new battery as it seems to work ok otherwise from what you have said.

[Horizon]

[quote="Dessie"]
I realise this has been covered before but I am looking for a bit of advice.

I was in the smug zone last year,setting my timer and coming out to a nice warm frost free car in the morning.

I set it last week and again last night and was rather disappointed to find nothing had happened either morning. The heater unit seems to be working ok as I had I had hot air within a couple mins of starting the car. When I got to work the little exhaust underneath was pumping hot fumes and was nice and hot itself. It runs on for a little while after I have switched the engine off.

I moved the car tonight to let my son out of the drive and there was steam /condensation coming out of the the exhaust almost immediately.

Can anyone suggest why the heater will not work without the engine running when it has in the past, both on timer and direct mode.

Thanks

Derek
[/quote] if you have used/ driven the car earlier today, and the water temperature Hasn't dropped below a certain temperature, it may feel that it's not needed. They were fitted on the E53 d to assist in getting the engine temp up quicker, and not on the e70,s as they heat up quicker .

[Dessie]

Thanks for the replies.

Can anyone tell me what the minimum voltage / state of charge should be.

My battery was changed for a Bosch Silver about 2 years ago but I do a lot of short journeys so I guess the charge could be a bit low.

I will check the voltage tomorrow.

[X5Sport]

Your battery should be showing around 12.6 if usable with much below 12.2 probably shutting it down.  Short journeys will not put enough charge back in as it takes approx 20 mins to put a starting charge back.  Might be worth buying a battery conditioner/charger to keep it topped up

[Dessie]

Thanks for that,

I have put my car on a slow charge over the weekend and will check the voltage tomorrow night and try the heater on Monday.

Watch this space.

[Dessie]

I charged my battery over the weekend and checked it last night - 12.7v, good to go.

Fired up the heater on direct mode and it fired up and ran for about 5 mins then shut down. The body of the heater was incredibly hot, I mean HOT. :'(

I am wondering if the circulation pump is US or if there is no signal to start from the main PCB. Does anyone know if it can be tested easily. Am I right in assuming there should be 12v on the connector to the pump when the heater is heating, I've heard about these K Bus thingys and the problems I may encounter.
I assume hot outlet and cold inlet are as marked. Is that the pump underneath?

[Horizon]

[quote="Dessie"]
I charged my battery over the weekend and checked it last night - 12.7v, good to go.

Fired up the heater on direct mode and it fired up and ran for about 5 mins then shut down. The body of the heater was incredibly hot, I mean HOT. :'(

I am wondering if the circulation pump is US or if there is no signal to start from the main PCB. Does anyone know if it can be tested easily. Am I right in assuming there should be 12v on the connector to the pump when the heater is heating, I've heard about these K Bus thingys and the problems I may encounter.
I assume hot outlet and cold inlet are as marked. Is that the pump underneath?





[/quote]

Wait until the coolant is cold,so when you remove the coolant filler cap it's safe.
Start the webasco up and you should see a jet of water just below the filler cap position.

[fenj66]

the item your pointing to in green is just a solenoid divert valve.
the electric water pump is below the passenger headlight at side of radiator. mine failed and i had the same symptoms as yours. the pumps are expensive tho if i remember. i got a second hand one from an e39.
as already mentioned, you can check the electric pump works taking off the radiator cap and seeing a strong jet of water near the top.

[Dessie]

Thanks again.

Checked tonight and no jet of water with the heater on. Nice strong jet with the engine running. I assume that's from the engine pump though.

I will check that there is 12v going to the pump with the heating on / engine off, just to be sure  ::)

[Dessie]

12v on multiplug  Replacement pump ordered. Can anyone tell me how to remove the hoses please?

[fenj66]

if i remember, the hoses are on a quick release system, i think you pull the wire clips off a little and they just pull apart.

[Dessie]

Thanks for that, I did wonder as I thought I could see some metal bits on the ends. Pump arrived today and not a moment too soon, -5 this morning  :xmassad:


Job for the weekend me thinks

[Dessie]

SORTED. Thanks again all. fenj66 -  the hoses were indeed o a quick release. I just put a small screwdriver in he little space and the clip pulls out then locks there. Simply pull end of pump.

20min total.

Happy boy.  :xmasgrin:

[fenj66]

glad its sorted!  did you get a second hand pump?