Perhaps God will smile and only a $15 coolant sensor is required,
photo here. It is about halfway down the passenger side of the radiator. Disconnect the wire, quickly screw the sensor out, screw the new one in, and reconnect the wire. The hardest part is getting stuff out of the way to reach it. Depending how speedy you are you will lose a bit of coolant.
If there is no obvious sign of escaped coolant the warning light may be an indicator a defective intake manifold gasket is permitting it to enter the engine. Coolant contaminated motor oil has severely diminished lubricating qualities. Catastrophic engine failure will occur very quickly. A competent mechanic should examine the van immediately. Trace evidence of an internal coolant leak is sometimes present near or under the throttle body area of the upper intake manifold. Replacing the gasket costs about $900. A rebuilt engine is probably worth more than the van.
CTV report here.
