No Heater this morning!
 

Last night it got down to 31 degrees and when we got ready to go to church we had no heat in the 2003 E320.
After church we drove for hours around to several relatives delivering Christmas gifts, with out heat.

The blower and everything seemed to work, only cold air came out no matter it it was the defrost or the floor vents.
I stopped at Harbor Freight and for $15 I picked up a 12V defoster/heater that got us through the day.

It used to be always the thermostat when the heat died but today I'm lost with all the sensors in cars today.

Any ideas where to start other than the dealer?

Thanks to all

More data needed
 

Clearly stating the year and model will help you get a quick useful answer.
You can also call me Monday.

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Coolant level low?

Remove the wipers.unscrew the cowl, under the cowl the electric heater valve is there , replace it common problem on that chassis when there is no heat

The very first line says that it's a 2003 E320.

X2

Sorry
 

I missed it.

The heater valve was superseded from MB# 2118320084 to MB# 2118320584

As I recall, the earlier valve was a common failure item.


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Can I do that at home?
 

Can I do that at home?

I've rebuilt engines in my early days, changed heater cores in GMC trucks.

Can I change that part at home?

Any special tools needed?

Thanks

I did it!
 

I had to wait for the part to arrive and I spent 4 hours changing the heater control valve in my barn.

I picked up extra O rings and I had to replace one. I picked up some extra Clips and had to replace one of those too.

But the job went great and I thank all who added to my question.

Total= 4 hours and $73

Thanks