Pressure in coolant reservoir, fan won’t start.
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Pressure in coolant reservoir, fan won’t start.
Hello all!
I have owned an ‘06 e350 for some many years now, but I gave it to my friend two years ago temporarily, and he went on a mission a year ago. So, the car had been sitting for a year before I decided finally get it back. Now that I have it, I have a coolant issue I cannot figure out.
My car temperatures rise concerningly high after being at operating temp for a bit, which told me obviously the cooling system wasn’t functioning. After driving short periods, the coolant reservoir overflows and leaks from the cap.
Due to all the pressure in the tank, I checked all the hoses and lines before realizing 2 things.
1. The coolant temp sensor had a wire cut that I have since reattached, but no difference came.
2. The engine fan doesn’t turn on at all. Ever.
I have suspicions that the issue still lies in the coolant temp sensor, as no difference was shown after reattaching a wire that was literally severed.
I had an issue years ago when the car sat in which the same wire was cut to the coolant temp sensor, however the engine fan would stay on and run at max speed the whole time, rather than not turn on at all. Since, I have swapped connectors to the coolant temp sensor with one from the junkyard, which worked till the wire in that on was cut also.
I apologize for the length, but if anybody can give me any insight into what to check and why this is happening, and more importantly, if there is an issue in my wiring job, which i have redone a couple times.
I will attach pics of my icarsoft codes when possible.
I have owned an ‘06 e350 for some many years now, but I gave it to my friend two years ago temporarily, and he went on a mission a year ago. So, the car had been sitting for a year before I decided finally get it back. Now that I have it, I have a coolant issue I cannot figure out.
My car temperatures rise concerningly high after being at operating temp for a bit, which told me obviously the cooling system wasn’t functioning. After driving short periods, the coolant reservoir overflows and leaks from the cap.
Due to all the pressure in the tank, I checked all the hoses and lines before realizing 2 things.
1. The coolant temp sensor had a wire cut that I have since reattached, but no difference came.
2. The engine fan doesn’t turn on at all. Ever.
I have suspicions that the issue still lies in the coolant temp sensor, as no difference was shown after reattaching a wire that was literally severed.
I had an issue years ago when the car sat in which the same wire was cut to the coolant temp sensor, however the engine fan would stay on and run at max speed the whole time, rather than not turn on at all. Since, I have swapped connectors to the coolant temp sensor with one from the junkyard, which worked till the wire in that on was cut also.
I apologize for the length, but if anybody can give me any insight into what to check and why this is happening, and more importantly, if there is an issue in my wiring job, which i have redone a couple times.
I will attach pics of my icarsoft codes when possible.
Thread Starter
Newbie
Joined: Oct 2024
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I actually just installed a new thermostat, and the coolant error message / fan issue is still there.
I will say though that the check coolant message went away, not sure if a coincidence or not. After a long drive (as long as possible without temps rising too much), there isn’t any coolant/excess pressure pushing coolant out the tank, but again it’s been one drive. It used to happen everytime, even in short drives.
I will say though that the check coolant message went away, not sure if a coincidence or not. After a long drive (as long as possible without temps rising too much), there isn’t any coolant/excess pressure pushing coolant out the tank, but again it’s been one drive. It used to happen everytime, even in short drives.
MBWorld Fanatic!
Joined: Feb 2017
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From: Baltimore County, MD
'13 s212 63 p30. '06 LX470
I actually just installed a new thermostat, and the coolant error message / fan issue is still there.
I will say though that the check coolant message went away, not sure if a coincidence or not. After a long drive (as long as possible without temps rising too much), there isn’t any coolant/excess pressure pushing coolant out the tank, but again it’s been one drive. It used to happen everytime, even in short drives.
I will say though that the check coolant message went away, not sure if a coincidence or not. After a long drive (as long as possible without temps rising too much), there isn’t any coolant/excess pressure pushing coolant out the tank, but again it’s been one drive. It used to happen everytime, even in short drives.
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Joined: Oct 2024
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MBWorld Fanatic!
Joined: Jun 2014
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From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
There's quite a few threads here on fan issues and look at the other forums like the W164 which are very similar. As the fans aren't coming on at all (you didn’t say if you've checked the fuses - assume you did) it's worth bench testing the fans to check their functionality including any relay. I'd be working from the fans back toward the engine rather than the other way around. Looks like there are plenty of reasons they don't come on - everything from sensors to the Ignition module and ECU. Post your VIN and I'll try and get you a diagram.
Last edited by BlackML550; Nov 16, 2024 at 12:00 AM.
