low coolant light randomly flashing.... STILL!!!

[R.O.R-2.0]

ok, so my low coolant light on my 92 has developed a new trick..

it just randomly starts flashing.. full of coolant, and cold engine.

light starts flashing.. turn key off and re-start a few times and it goes out like it should be.. sometimes it goes out on its own, sometimes it stays on. literally has a mind of its own..

this car is really getting on my nerves, and im almost ready to rip all the electrical out of it and swap in my german GLI harness..

[bajacalal]

Check the connectors.

I was having an issue like this, the connector on the temp. sensor was working loose. A zip tie corrected it.

[guy plain]

I was having an issue like this, the connector on the temp. sensor was working loose. A zip tie corrected it. 
 
 same here but it was a cracked wire...

[R.O.R-2.0]

my connector at the temp sensor is less than 2 weeks old tho 

[shwak23]

Maybe the sensor on the Coolant Rez is busted? Or that connection there is dirty or loose... Go out and wiggle some stuff breh. 

[fatmobile]

 The coolant level sensor needs a certain voltage across it.
 You can pull the boot back and stick a voltmeter to the contacts.
 Sometimes the ground side is not grounded well enough, which will cause the voltage to jump high.

[R.O.R-2.0]

The coolant level sensor needs a certain voltage across it.
 You can pull the boot back and stick a voltmeter to the contacts.
Sometimes the ground side is not grounded well enough, which will cause the voltage to jump high.

thinking this be my issue.. it will flash like no other if i have NO accessories turned on. turn ANYTHING on (heater fan, window defroster, cruising lights, whatever) and the light goes out..

where is the ground for this bad boy located? ive already treated the contacts with cleaner/protection spray, and no dice. still randomly flashes, and reservoir still be full..

what voltage am i looking for at the contacts, when i check it?

[fatmobile]

It's been awhile since I messed with this,.. I rebuilt the MK2 circuitry to bolt to the back of the instrument cluster So I could have a low coolant level and overheat warning light in the Rabbit.
 I can't remember what the trip voltage was across the level sender,... seems like 3.5 or 5 volts, something like that.
 Since my experience is with Rabbits that didn't have the sender stock,..; I don't know where it grounds to.
 I'm thinking shock tower nearby.

[Baron VonZeppelin]

RoR
my 85 was doing something similar to what you describe when i first got it.

Did some checking of things in general, then put in a New Meyle coolant sensor - about $5. Cure.

Have you already tried swapping in some various used ones yet ?

[R.O.R-2.0]

RoR
my 85 was doing something similar to what you describe when i first got it.

Did some checking of things in general, then put in a New Meyle coolant sensor - about $5. Cure.

Have you already tried swapping in some various used ones yet ?

the sensors are part of the coolant bottle..

[Baron VonZeppelin]

ahh okay

you've got the newer stuff with the globe - my fault.

If you jump the wires together, and condition persists,
that would eliminate the sensor in the globe being culprit. 

[JessaBug]

Our coolant light flashes all the time too. Can't really figure out why. Got a new sensor, coolant is full. Oh the joys of VW wiring...

[Baron VonZeppelin]

An mk2 with ce1 i worked on last year had an issue with either the battery indicator or the oil press indicator staying on (forget which). Swapped in another cluster and it went right back to being normal.

If you guys have spare clusters (even a gas cluster) could give that a try.

On that one, they wanted to retain the orig speedo into replacement cluster.
So they did that themselves to save a buck.
And the previous symptom followed along with their old speedo pod. lol

So i had to swap their old speedo guts into the replacement cluster speedo pod for them. Fun stuff for everyone as usual.

[R.O.R-2.0]

An mk2 with ce1 i worked on last year had an issue with either the battery indicator or the oil press indicator staying on (forget which). Swapped in another cluster and it went right back to being normal.

If you guys have spare clusters (even a gas cluster) could give that a try.

On that one, they wanted to retain the orig speedo into replacement cluster.
So they did that themselves to save a buck.
And the previous symptom followed along with their old speedo pod. lol

So i had to swap their old speedo guts into the replacement cluster speedo pod for them. Fun stuff for everyone as usual.

i only have 1 CE2 cluster.. and i dont think its the cluster, to be honest. i can load my electrical system a bit, and get the light to go out.. turning on the window defroster, headlights, heater fan, anything like that turns the light off..

someone was saying that the voltage going HIGH on the sensor, will make it go off.. and that would go right along with my problems.

[fatmobile]

Checked the voltage across the sensor?
 Or sensor postive to ground?
 How about sensor ground to ground at battery?