Q: Trying to diagnose a po405 Low Signal circuit voltage to egr. Everything working fine but code will not go away??

asked by on January 19, 2017

Tried diagnosing without any luck finding problem

My car has 125000 miles.
My car has an automatic transmission.

Hi there. P0405 is an OBD-II generic code that the engine control module (ECM) detected the engine exhaust gas recirculation (EGR) sensor has went below its specification range. A short to ground of the sensor input to the ECM. You might want to read this article as it will give you several tips on how to diagnose the problem and root source.

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