coolant level warning light

jwthwaites96 · Post by **jwthwaites96** » Tue Jul 29, 2008 5:21 pm

hi guy's, i am very happy to say since i last wrote on here that the car was on its way out, its risen from the flames and is flying strong (thanks to doc)...... well kind of.
new issue - the coolant level warning light on the dash keeps coming on, from cold its off but drive for lets say 1.5mile it then flashes up and you can't get rid of it. and then at work it cools for say 5 hours and it will still be on when you start it up after. Any suggestions?

Cheers

Kitch · Post by **Kitch** » Tue Jul 29, 2008 6:26 pm

If it's got an expansion tank setup, I'd try changing the sensor or first checking the connections (assuming it isn't actually low on fluid?)

jwthwaites96 · Post by **jwthwaites96** » Tue Jul 29, 2008 6:37 pm

nope its very much full, bleeded it from all bleed valves and still comes on.
it does not have a extra tank that i know of (if it did where would it be, it is a BX TZD 1.9 H reg if that helps you).
when you say connection do you mean one of the elctrical connections on the top of the thermostat housing? is that just a case of checking they are connected properly, i will check that but if that is the case why is it not permanently on and only on when the engine seemidly gets hot?
cheers

Post by **docchevron** » Wed Jul 30, 2008 2:25 am

Er, if there's water in the rad, then it's most likely an electrical issue.

Is there still a leak?

Now, which light is coming on?

The low level light, or the over heating lamp of death?

The low level light is triggered from a sensor half way down the rad on the same side as the filler neck.

It was disconnected when the rad came out, so it's possible there's a dodgy connection there.
But if it's only coming on when hot it makes me wonder if the light you refer to is actually the lamp of death, in which case things need to checked urgently.

jeremy · Post by **jeremy** » Wed Jul 30, 2008 7:20 am

As you know there were 2 engine options for the TZD - the 1.9D which you have and which has the expansion tank incorporated with the radiator (and in fact in the end of the tank under the cap) and the 1.7 turbo-diesel which has a separate expansion tank and filler basically in the middle of the under-bonnet space (Same component as the 16 valve)

The coolant level light is in the strip of lights in the centre of the instrument panel and is below the ignition warning lamp. The symbol is a traditional radiator or something and it should light for check purposes when the engine is stationary with the ignition switched on.

The drivers handbook (in fact an edited version covering both petrol and diesel) is available here:

http://www.rwbsmith.plus.com/citroen2/

jwthwaites96 · Post by **jwthwaites96** » Wed Jul 30, 2008 4:38 pm

Well guy's after all this talk of lamp of death and everything i went and checked, it is definatly the coolant level light, phuwwww! in the middle of the dash, comes on when engine is turned on and then switches of when engine is turned over.
I have checked the connection of the electrical bits, seem to be connected, this is why i am confused why it is not always on. As for the expansion tank i the top of the rad filler hole area, did not know this, level is at the normal level rather than coming up the neck of the rad filler.
Any more suggestions
Cheers

jeremy · Post by **jeremy** » Wed Jul 30, 2008 6:27 pm

The coolant level lamp is linked to the oil pressure light for testing purposes - as are one or two others. The idea is that you turn the ignition on - light shows, start engine - light extinguishes - using the oil pressure system as a timer.

The oil pressure light itself turns on the STOP light I think if oil pressure fails while you're driving - as does the hydraulic pressure and level warnings. I don't think the coolant level light does.

However if the engine stalls or looses oil pressure - the coolant light will probably come on as well making for an impressive display!

I'd check and clean the switch connectors as a first action. Connectors on these cars can acquire some rather impressive corrosion which is very difficult to shift. (later Citroens seem better!)

I

jwthwaites96 · Post by **jwthwaites96** » Wed Jul 30, 2008 8:06 pm

by cleaning the connectors do you just mean disconnecting them and scrubbing the metal till it shines? what do you mean by oil pressure failing, as far as i know that is at the right level, would too much or too little oil cause that to happen?

ellevie · Post by **ellevie** » Wed Jul 30, 2008 8:42 pm

I had a similar problem with my BX19TXD when I got it about 18 months ago. I traced the problem to poor connectivity in the connector to the water level sensor that doc mentions "half way down the rad on the same side as the filler neck." I sprayed some WD40 on the contacts of the plug and socket and then pushed the connector on and off a few times to clean the contacts. This cured the problem and it hasn't returned since.

jeremy · Post by **jeremy** » Wed Jul 30, 2008 9:38 pm

The water level light is meant to come on when you turn on the ignition - before the engine starts. This is for test purposes - to show that the bulb still works!

To achieve this miracle in communications it is necessary to provide a power source that will switch off after the test has been conducted and you've had time to observe the results - so they connect it to the oil pressure light - which of course comes on when the ignition is switched on and with luck goes out when the engine starts.

They could have used a computer to power the thing but they were reserved for more important functions on 1980's cars - like the red temperature warning light (amber is light of death - red probably means cremation), fuel injection and ABS and probably some others.

Mike E (uk) · Post by **Mike E (uk)** » Wed Jul 30, 2008 11:03 pm

there is a small black plastic box connected by the o/s end of the rad,
that is something to do with the coolent level sensor, give the connections to this a good clean, it cured a low coolent level 'problem' for me.

jwthwaites96 · Post by **jwthwaites96** » Fri Aug 01, 2008 4:58 pm

Hi guys,
cheers for all the advise, yep it seems its the connector is a bit dirty/ corroded, going to have a good clean of it at the weekend, thanks again for all the help.
J

DLM · Post by **DLM** » Fri Aug 01, 2008 5:53 pm

The 12-pronged low level indicator relies on a (weak) current passing through the coolant from one prong to the other. I've seen false alarms come from this on a couple of 1.9Ds.

(i) If the prongs become furred-up or otherwise coated, the level light comes on.
(ii) An airlock would also do the same.

Unfortunately, the only way to check is by removing the sensor, which isn't possible without spilling/draining a fair amount of coolant.

DLM · Post by **DLM** » Fri Aug 01, 2008 5:54 pm

12-pronged? 2 pronged, more like. Dohhh!

Post by **docchevron** » Sat Aug 02, 2008 2:51 am

12 prong!
Now thats an EPIC low water warning sensor!

FTW!

Hows things Dave? You've been very quiet lately.