Warning lights stay on

CHCHCH60

MEMBER
1999 LINCOLN CONTINENTAL
V8
AUTOMATIC
125,000 MILES

My car displayed low coolant level warning. I checked and it was low so I topped it off. Then I noticed a puddle of antifreeze in the garage and the car would not heat up.
I took it in to the mechanic and they found a leak and had to replace the water pump as well as the belt which had been soaked in antifreeze.
When I picked up the car it had great heat, no leaks but the warning light was still on. Any now, a few days later, it still comes on. I reset it and a while later it is back on. The mechanic is stumped too.
Any ideas on how to get this warning to keep from coming on?

1 Reply

PATENTED_REPAIR_PRO

MECHANIC
1,853 POSTS

Follow this test:
Test e: low coolant warning never/always on.

1. Ensure coolant reservoir is full. Turn ignition switch to "off" position. Disconnect coolant level sensor harness connector C148. Turn ignition switch to "run" position. Measure voltage at light blue wire terminal at coolant level sensor harness connector C148. If voltage is greater than four volts, go to next step. If voltage is four volts or less, go to step three.
2. Turn ignition switch to "off" position. Measure resistance between ground and black wire terminal at engine coolant level sensor harness connector C148. If resistance is five ohms or less, go to step four. If resistance is greater than five ohms, repair open in black wire.
3. Disconnect instrument cluster harness connector C256. Measure resistance in light blue wire between engine coolant level sensor harness connector C148 and terminal number seven at instrument cluster connector C256. See figure. If resistance is five ohms or less, go to next step. If resistance is greater than five ohms, repair open in light blue wire.
4. Measure resistance between coolant level sensor terminals (component side). If resistance is greater than five ohms, replace coolant level sensor. If resistance is five ohms or less, replace instrument cluster.

That switch is #43 in this diagram, and it's located under the hood by the right shock tower.

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