RADI Light On; Did I do that?

[sgtncharge]

Oh man, Did I do that? I forgot about how Murphy's Law applies to me when I work on vehicles. I gave My van a long over due tune-up yesterday. Replacing the spark plugs, wires, cap, rotor and air filter. I cleaned up the engine a little with some W-D40 and rags and tightened a couple of the belts. I put everything back together and drove it a mile down the road to the car wash. left it running during the automatic wash, and while I waited at the fast food drive thru. While waiting the oil light had come on. No problem, I knew I needed to add oil. I just forgot. So I head back to the house with my food, a clean van and a smile on my face because of a job well done. I added oil to the motor and called it a night. Altogether the van was running about 30 minutes. All was fine. Ran great and better than it has since I got it about 6 weeks ago. Then this morning I go out and head to the store for some cigarettes. But before I can get out of the driveway or about a minute after starting the engine, the RADI light comes on. I'm thinking Oh crap! WTF did I do? I wonder if I tightened the fan belt too tight or maybe I accidentally unplugged a sensor or maybe I forgot to plug something back in. I don't know. I looked around and saw nothing visibly out of place. I noticed the radiator fan was working. I looked in the coolant reservoir and it was below low a little bit so I added water to it. I removed the radiator cap and added about a quart of water to top it off. Altogether about 1 1/2 quarts of water was added. I started it back up hoping the light would be off but it wasn't. So, now I don't know what to do. Ohh Timmmmmmm.... or somebody, you got any ideas? It's got to be something simple right?

[djshimon]

Radiator light means imminent implosion-stand back!! April Fools! Are you sure it's the radi-light? There is a sensor in the radi-overflow with a wire going out the bottom. If there is liquid in there the light should go off. If not, bad sensor(stuck closed) or bad wiring. The wire that comes off the overflow can be disconnected and the light then goes off-about a foot down the wire there is an electrical connector, unplug it.
If you keep losing coolant it could be a simple hose, or worse...

[timsrv]

If the overflow bottle is full and the radiator light is on, then unplug the blue connector to the overflow bottle. If the light goes out then the problem is a stuck float in the overflow bottle. If the light stays on then the problem is someplace else in the circuit............possibly a grounded wire between the overflow bottle and the warning light.

[sgtncharge]

If the overflow bottle is full and the radiator light is on, then unplug the blue connector to the overflow bottle. If the light goes out then the problem is a stuck float in the overflow bottle. If the light stays on then the problem is someplace else in the circuit............possibly a grounded wire between the overflow bottle and the warning light.

OK, I unplugged the connector and the light goes out. So, the problem is a stuck float. Is there anyway of freeing up the float? Maybe cleaning it somehow? I don't see any bolts holding the overflow bottle on. How is the bottle attached? Or maybe I can drain it to see whats going on down inside. Is there a drain plug on the bottle?

[gushaman]

the overflow bottle sort of clips onto its bracket. grasp it firmly, and pull it straight upwards.

[User1]

You may want to check that little float thing in the overflow tank. I discovered mine doesn't float at all! You should be able to move that by hand if the tank is empty. I was able to turn mine off and on by moving it by hand. I'll have to work on the replacement.