stinkin blinking coolant light

wjlund · Post by **wjlund** » Fri Feb 16, 2007 4:02 pm

85 Jetta TD Coolant Light will continue to blink when the engine is cold and will continue until the engine is turned off. When you restart it (engine now warm) light stays on 5 sec (normal) and then goes off. What I've done: Changed sensor in tank, replaced coolant relay. Any thoughts on this one? Thanks

VanagonMark · Post by **VanagonMark** » Fri Feb 16, 2007 5:08 pm

Either your sensor in the water bottle is bad, or you have a bad connection somewhere in the ignition area

Pull the wires on the water bottle and cross the two connections, see if you still have the problem

bet its that sensor

Vincent Waldon · Post by **Vincent Waldon** » Mon Feb 19, 2007 2:27 pm

On mine the connector that plugs into the top of the sensor was intermittent.. combination of age and the wires bending at a sharp angle as they leave the top of the bottle. The warning circuit is a latch, meaning once it trips for any reason it will flash forever until you cycle the ignition, so it's hard to track intermittents down. My guess at the time was the extra rattling during a cold start was shaking it bit much.

Turns out the connectors that plug into the upshift light switches on my injection pump were exactly the same connector.. I'll long ago disconnected the upshift light so had a couple of spares... spliced one in... problem solved.

I've also seen this once with a dirty sensor (oily.. ack) but if you just changed it that's unlikely.