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customer came in with fan always on and a check engine light
codes:P0118 ect voltage high
power side of the ect should be 5v instead its 12.7 with engine running
i followd the wire to the pcm and it giving 12.7 v (no short to voltage)
note ;sensor was replaced
do you guys think i should replace the computer?
thank you
Unplug the ecm connector that contains that ECT 12.7v wire from the ecm and check the voltage at the corresponding ecm pin koeo. Sorry, don't have a wiring diagram to give pin number.
I'm thinking why don't you have other 5v ref on other sensor showing 12.7v. A problem with the ECT 5v ref will not bring down the entire 5v ref circuit because of the internal resistor, but I still wonder. Check the TPS. You could use the 5v ref from TPS for ect. ECM is expensive.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
i pulled out the wiring diagram and followed the wire to the ecm(pin12) i then cut the wire and had the engine running and still giving 12.7v
all other 5v ref circuits are working normal
do you think their is any other variable?
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