Assume you mean it hasnt happened since you reset the light.
If it says "circuit malfunction" that would be the switching circuit itself.
I would assume it might be either in the wiring or the valve actuator
solenoid itself; in which case, inspect, and clean, replace (solenoid) as
- Yes, I'm a crusty old geezer curmudgeon.. deal with it! -
The P0412 code does not mean "replace part xxx", it meand the fault lies in
subsystem. IIRC, there were some problems with water ingestion into the pump on
system. I would suggest buying the factory service manual on CD (Available all
Ebay for ~10.00) Here's one-
Follow the troubleshooting proceedure. I believe there are 3 main parts to this
system: an electrical pump, solid state relay, and the switching valve. All 3
pricy items. Certain pump failures can cause P-0412 to set. Inspect the
piping, The pump and relay are located low on the left front of the car, near
bottom corner of the radiator. The valve is located near that corner of the
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