P0347

P0347 means the Bank 2 CMP A signal voltage has dropped below the ECM's low threshold (typically under 0.2V on a 5V Hall-effect circuit, or essentially flatline on a VR sensor), which the PCM reads as either a shorted-to-ground signal wire or a dead sensor. Cheapest-first ladder: unplug the Bank 2 CMP connector with key-on, engine-off, and backprobe the signal pin - it should snap up to the 5V reference. If it does, the sensor is internally shorted or the reluctor air gap is wrong; install a new sensor and verify air gap to spec (typical 0.020 to 0.050 inch). If the signal wire stays near 0V with the connector unplugged, the wire is shorted to ground between the sensor and the PCM - backprobe at the PCM connector to localize the short. Verify the 5V reference at the sensor connector reads 4.9 to 5.1V key-on. Check the sensor ground pin for under 0.1 ohm continuity to PCM ground. On Hall-effect CMPs the healthy live signal toggles 0 to 5V square wave at cranking and idle; on VR sensors the signal swings from ~0.5V peak-to-peak at cranking up to 3 to 8V at idle. The expensive misdiagnosis is replacing the CMP sensor when the real fault is coolant or oil intrusion into the connector shorting the signal wire to the shield - dry, clean, and dielectric-grease the connector before condemning the sensor or a chasing a PCM driver.

Vehicle-specific patterns: 2007-2014 Ford 3.5L Cyclone V6 (Edge, Flex, Taurus, F-150 EcoBoost) gets coolant intrusion into the Bank 2 CMP harness from a leaking rear cylinder-head plug, shorting the signal to ground. 2010-2016 Hyundai/Kia 3.3/3.8 Lambda V6 sees the Bank 2 CMP pigtail chafe against the engine lift bracket, shorting the signal wire after 80k miles. 2008-2013 GM 3.6L LY7/LFX has known TSB coverage for Bank 2 CMP signal-wire corrosion at the under-intake splice pack. 2007-2013 Nissan VQ35DE/VQ40DE Bank 2 CMP can fail internally shorted after valve cover gasket oil intrusion saturates the sensor body. 2011-2018 Chrysler 3.6L Pentastar Bank 2 CMP fails internally shorted in batches - check for a TSB-covered updated sensor revision before throwing parts at it. Estimated repair: $60 to $320.