Coolant Warning Light!?

[Guest Wheres_my_wig]

Hey up ,first post.

 

Right, my coolant warning light is flashing at me when i put my foot down. It wont come on until around 2500 - 3000 revs,

and if you floor it after that it will stay on until you take your foot off. Doesnt happen all the time, most the time not at all.

 

It was happening when i first brought the car, so i took it to peugeot and they drained and replaced the coolant. Seemed to fix it for about 3-4 months, and its come back with a vengance god damn. Engine sounds fine, doesnt feel any different.

 

Coolant level is topped up with proper stuff, doesnt look rusty but it was when it was drained the first time ect.

 

Any ideas on what this could be? Possibly a faulty sensor or something or could it be telling the truth and there is something wrong.

 

As much feedback as possible would be appreciatted! Happy to answer questions if you need more info

 

Cheers,

 

Dan

[Fox 3]

Does the gauge go to the top/red aswell? Or just the light?

[Rob Thomson 6]

You mean the collant level warning light in the middle of the dash, or the coolant temperature light at the top of the temperature gauge?

[Guest Wheres_my_wig]

Ahh sorry chaps. I mean the coolant level warning light, in the middle of the dash. Also, coolant and oil temps all fine too.

[DrSarty 90 1 Cars]

As it's only the coolant warning light, you have very little to worry about, as you've said the levels are fine.

 

For pence from a breakers you'll be able to get a new cap & plunger thingy. I suspect a swap of those will cure it.

 

As it's just an earthing circuit, i.e. float drops down, connects to wires/contacts to complete the dash bulb's earth circuit, it's highly likely that either your level is lower than it should be and it's working fine.

 

OR the float's making the circuit when it shouldn't, either coz it's buggered (perhaps a few sprays with WD40 and shake it about a bit) and needs fixing (perhaps a few sprays with WD40 and shake it about a bit)/or replacing.

 

OR the wires in the circuit somewhere have been bared to earth/metal and complete the circuit when you lurch the car about.

 

This should be a doddle to sort chief. But these things were sent to try us eh?

[Rob Thomson 6]

If you're sure the coolant's at the right level the problem can only be with the warning light system itself.

 

Have you got an early car with a clear coolant header tank, or is it one of the later ones with a black tank?

 

If it's got a clear tank you can simply remove the sender unit from the top of the tank, it just unscrews once you've disconnected the wiring. It's probably worth cleaning up the two electrodes and trying it again.

 

On the later tanks the sender clips in from underneath, which means draining some of the coolant as/before you take it out which makes the same job a bit more of a faff. Probably still worth trying, though.

 

If the senders are clean the problem's probably electrical. I know on my old 309 (which had a clear tank) there was a little black box at the front of the car by the radiator that controlled the warning light. I couldn't tell you whether there's something similar on a 205 or where it is (but there certainly isn't anything like that in the engine bay on my 1992 1.6 which has a black header tank).

[Rob Thomson 6]

i.e. float drops down, connects to wires/contacts to complete the dash bulb's earth circuit, it's highly likely that either your level is lower than it should be and it's working fine.

I've always thought the senders work by completing a circuit through the coolant? The senders are two copper prongs that hang in the header tank, like a pair of electrodes. But now I stop and think about it that seems unduly complicated and perhaps I've always managed to miss something fundamental (like a float!).

 

If I'm right, there's got to be some kind of electronic magic box somewhere that monitors the sender and controls the warning light, and that could easily be your problem.

[2052006 10]

I've always thought the senders work by completing a circuit through the coolant? The senders are two copper prongs that hang in the header tank, like a pair of electrodes. But now I stop and think about it that seems unduly complicated and perhaps I've always managed to miss something fundamental (like a float!).

 

If I'm right, there's got to be some kind of electronic magic box somewhere that monitors the sender and controls the warning light, and that could easily be your problem.

 

 

That's what I thought the two prongs did - no float (ph 2 tank). Certainly when I had this exact problem, all it took was removal of the sensor and cleaning it up - the two prongs were all furred up, so I thought this must have interferred with the current? Didn't really understand it but problem solved though!

[pug_ham 240 3 Cars]

Has your car got the black expansion tank?

 

If so these are very susceptable to the HT leads causing interference that make the light flash on occasionally. Try re-routing the leads as best you can away from the sensor (its in the bottom of the tank) & see if it stops. Its worked for a few people on here before.

 

Obviously check you have enough water in, if this light comes on & you are low on water you're supposed to stop immediately & top the system up before carrying on.

 

Gaham.

[Guest Wheres_my_wig]

Thanks chaps, been more than helpful, Shall be baring my problems more often. I've got a clear/white tank and will be taking a look tonight. Sounds like it shouldnt be too difficult. I'll let you know how i get on. Glad to know there shouldnt be any underlying problems.

[Guest Wheres_my_wig]

Well i had a look today, turns out it was just a loose wire at the bottom of the black expansion tank on the sender box. (though it was clear from memory!) taped it up and happy days. job done.

[DrSarty 90 1 Cars]

Well done Wiggaz.

 

You can close the topic now bud.

 

Down the bottom, mod options, in there.