LT, Crafter & Sprinter Tech - Coolant Light On & Temperature Max w/ Cold Engine

Coolant Light On & Temperature Max w/ Cold Engine

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Printed Date: 20 Apr 24 at 08:44
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Topic: Coolant Light On & Temperature Max w/ Cold Engine

Posted By: Junk
Subject: Coolant Light On & Temperature Max w/ Cold Engine
Date Posted: 26 Apr 18 at 16:30

Hi everyone, I've been reading the forum for a while but decided to make an account now I have a problem which I believe no one has yet mentioned. I'm a newbie with vans and mechanics so my question may have an obvious answer.

I've got an LT 35 2.4 TD from 1995 (thats LT1)

As soon as I put in the keys, before I turn ignition, the temperature gauge rises to the max and the coolant light (that is, the light next to the temp. gauge) starts blinking.

My coolant is at a good level. The engine cannot be overheating because this happens even when the car has been off overnight or for days, and the engine is cold.

I bought the van half a year ago from a friend who told me he never encountered this problem before. The problem arose during a long drive (2000km).

Does anyone have an idea what might be the problem?

Replies:

Posted By: nooberdoober
Date Posted: 26 Apr 18 at 21:54

Could it be the Earth behind the water bottle, drivers side footwell? Sounds not much different from something that happened on mine, though mine is a bit older....They get wet down there perhaps from dodgy seal on the indicator light or perhaps windscreen trim.

Check it out. If its rusted up, give it a good old scrub, get it back to clean metal, make sure all the crimp terminals are in good order and stick some silicon grease on each one.

That's the easy earth to get to. Other one to check is behind dash insert and requires more faff. Likelihood though is that one will be totally clean and fine, but maybe check anyway if you can with cheap wire-cam endoscope for your mobile phone off fleabay. That'll save you unscrewing the whole dashboard.

Also, perhaps good idea to unscrew your little sender unit from the header tank and give it a clean of all the brown sediment. Someone recently reported that this fixed their red light issue. Make sure that also has a good electrical connection.

On petrol ones, there is also a little heat sensor switch screwed into the water jacket on the back of the head. Not sure if same on diesel. Worth a check also that it has good electrical connection.

That should give you something to start with.

-------------
I got me a 2.4 straight Six......and it's a soundin JUICY!

1984 LT40 2.4 petrol Coachbuilt Autotrail Motorhome

Posted By: Junk
Date Posted: 06 May 18 at 12:20

Sorted!

When I unplugged the coolant temperature sensor (the four pinned one) and started the engine, the temp gauge stayed at zero and the light didn't flash. Seeing that this was where the dodgy signal was coming from, I was suspicious that the problem was either with the sensor or the wiring which came from it.

I took out the coolant temperature sensor (I guess that's what you referred to as sensor unit) for a clean but still it gave the same reaction.

Then I took it out again, dried it off and gave it a few hits against the wall. There was a small amount of liquid where I hit it. Then I saw that there was a microscopic crack in the sensor which coolant fluid had absorbed into, hence the dodgy signal.

I bought a replacement coolant temperature sensor and everything was fine.